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1

O "rompimento da caixa" e suas conseqüências na prática do projeto residencial no século XX.  

E-print Network

??Esta dissertação objetiva mostrar conseqüências ocorridas na prática do projeto residencial provenientes do ¿rompimento da caixa¿. O trabalho investiga um conjunto de residências unifamiliares concebidas… (more)

Merlin Janina Diemer

2006-01-01

2

Evoluzione della vegetazione nei pressi del Lago di Lavarone (TN) negli ultimi 2200 anni  

Microsoft Academic Search

RIASSUNTO - Evoluzione della vegetazione nei pressi del Lago di Lavarone (TN) negli ultimi 2200 anni - Lo studio pollinico e paleolimnologico della sequenza S5 proveniente dal Lago di Lavarone, condotto nel corso del progetto OLOAMBIENT, ha permesso di ottenere un quadro dettagliato sull'evoluzione del territorio nei pressi del lago negli ultimi 2200 anni. Sulla base delle informazioni archeologiche e

Enrico ARPENTI; Maria Letizia FILIPPI

3

CP Violation and K0 decays revelation: study and simulation of neutral Trigger in NA48 experiment -- Violazione di CP e rivelazione dei decadimenti del K0: studio e simulazione del Trigger neutro nell'esperimento NA48  

E-print Network

At the INFN laboratory in Pisa I have prepared my dissertation, which essentially concerned Montecarlo simulation of subnuclear particles decays and investigation of low-noise electronic devices for analyzing high-frequency signals. The team-work was part of NA48/EPSI experiment jointly carried out with European Organization for Nuclear Research CERN, Geneva. ----- Nell'ambito dell'esperimento NA48 in corso al CERN Super Proton Syncrothon (SPS) finalizzato a misurare la violazione diretta di CP in sistemi di particelle K0 attraverso il doppio rapporto R = [N(K_L->Pi0Pi0)]/[N(K_S->Pi0Pi0)] / [N(K_L->Pi+Pi-)]/[N(K_S->Pi+Pi-)] = 1 - 6 Re(e1/e) con una precisione di Re(e1/e) superiore a 2 * 10^-4, il lavoro di tesi si propone di effettuare una simulazione per la rivelazione dei decadimenti neutri dei K0 ed una successiva analisi dei dati raffrontando l'evento fisico generato con metodo Montecarlo e quello ricostruito. Per la misura di e1/e occorre isolare tra i vari modi di decadimento dei K quelli K_S->Pi0Pi0, K...

Calzolari, F

2007-01-01

4

CP Violation and K0 decays revelation: study and simulation of neutral Trigger in NA48 experiment -- Violazione di CP e rivelazione dei decadimenti del K0: studio e simulazione del Trigger neutro nell'esperimento NA48  

E-print Network

At the INFN laboratory in Pisa I have prepared my dissertation, which essentially concerned Montecarlo simulation of subnuclear particles decays and investigation of low-noise electronic devices for analyzing high-frequency signals. The team-work was part of NA48/EPSI experiment jointly carried out with European Organization for Nuclear Research CERN, Geneva. ----- Nell'ambito dell'esperimento NA48 in corso al CERN Super Proton Syncrothon (SPS) finalizzato a misurare la violazione diretta di CP in sistemi di particelle K0 attraverso il doppio rapporto R = [N(K_L->Pi0Pi0)]/[N(K_S->Pi0Pi0)] / [N(K_L->Pi+Pi-)]/[N(K_S->Pi+Pi-)] = 1 - 6 Re(e1/e) con una precisione di Re(e1/e) superiore a 2 * 10^-4, il lavoro di tesi si propone di effettuare una simulazione per la rivelazione dei decadimenti neutri dei K0 ed una successiva analisi dei dati raffrontando l'evento fisico generato con metodo Montecarlo e quello ricostruito. Per la misura di e1/e occorre isolare tra i vari modi di decadimento dei K quelli K_S->Pi0Pi0, K_S->Pi+Pi-, e quelli K_L->Pi0Pi0, K_L->Pi+Pi-.

Federico Calzolari

2007-01-15

5

Variación mensual en el aporte de hojas de cuatro especies forestales nativas del Parque Chaqueño Húmedo (Argentina) Monthly variation of the litterfall in four forestal native species from the Humid  

Microsoft Academic Search

El objetivo del trabajo fue cuantificar la cantidad anual de hojas aportadas al suelo proveniente de cuatro especies forestales nativas del Parque Chaqueño Húmedo, y su relación con algunos elementos del clima, como precipitaciones, temperaturas mínimas mensuales, velocidad del viento, heliofanía relativa. Se ubicaron 5 parcelas de 1000 m 2 cada una y se seleccionaron cuatro especies forestales de importancia

J. Prause; G. Arce de Caram; P. N. Angeloni

2003-01-01

6

Posibles implicaciones de la legalización del consumo, Producción y comercialización de las drogas en Colombia  

Microsoft Academic Search

Como reacción ante el aparente fracaso de la estrategia represiva de lucha contra las drogas ilícitas y debido al incremento considerable del conflicto en Colombia, el debate sobre las bondades y males de la legalización ha cobrado especial interés en el país. Propuestas provenientes de distintos sectores sociales, políticos y académicos coinciden en que para desincentivar el negocio del narcotráfico,

Andrés VERGARA BALLEN; Yilberto LAHUERTA PERCIPIANO; Sandra Patricia CORREA

2003-01-01

7

Futuro de las telecomunicaciones en México ¿Cuál debe ser el rol del gobierno ante los nuevos escenarios del mercado?  

Microsoft Academic Search

El objetivo del presente artículo es analizar las decisiones de política pública que está llevando a cabo el gobierno de México para impulsar la competencia en el mercado de telecomunicaciones. Para ello, se identifica la forma en la que está organizado este sector y se utilizan herramientas provenientes de la teoría económica de redes para evaluar las acciones de este

Fernando G. Toriz Flores

2010-01-01

8

Espectroscopia del Cometa Halley  

NASA Astrophysics Data System (ADS)

Se reportan observaciones espectroscópicas del cometa Halley. Los espectros fueron tomados usando el espectrógrafo del telescopio reflector de 1 metro del Observatorio Nacional de Venezuela. Se utilizó óptica azul, con una red de difracción de 600 lineas/min, obteniéndose una dispersión de 74.2 A/mm y una resolución de 2.5 A, en el rango espectral de 3500 a 6500 A. Seis placas fueron tomadas con emulsión IIa-O y dos con IIa-D. Los tiempos de exposición fueron entre 10 y 150 minutos. El cometa se encontraba entre 0.70 y 1.04 UA del Sol, y entre 1.28 y 0.73 UA de la Tierra. Las emisiones más prominentes en el espectro, son las del CN, C2, y C3. Otras emisiones detectadas corresponden a CH, NH2 y Na. Los espectros muestran un fuerte continuo, indicando un contenido significativo de polvo. Se detectó mayor intensidad del contínuo, en la dirección anti solar, lo cual es evidencia de la cola de polvo.

Naranjo, O.; Fuenmayor, F.; Ferrin, L.; Bulka, P.; Mendoza, C.

1987-05-01

9

Origen y evolución de la estructura del Universo  

NASA Astrophysics Data System (ADS)

Se presenta una revisión de diversos tópicos vinculados a la evolución de estructuras en el Universo y se discuten los escenarios más aceptados para la comprensión de las irregularidades primigenias y de su evolución temporal. Se analizan evidencias observacionales de la naturaleza jerárquica en los mecanismos de formación de sistemas, tales como las indicaciones provenientes de las correlaciones espaciales y de velocidades, la naturaleza del Universo a alto redshift, y la habilidad de los modelos jerárquicos en predecir diversas propiedades dinámicas, fotométricas y químicas de las galaxias.

García Lambas, D.

10

Atlas del Genoma del Cáncer  

Cancer.gov

Es posible que haya más de 200 tipos diferentes de cáncer y muchos subtipos más, cada uno de estos causado por errores en el ADN que desencadenan el crecimiento descontrolado de las células. La identificación de los cambios en el conjunto completo de ADN de cada tipo de cáncer, su genoma, y el entendimiento de cómo interactúan dichos cambios para impulsar el proceso de la enfermedad sentarán las bases de una era individualizada de tratamiento del cáncer.

11

Ciclo de vida del VIH Enlace y fusin: El VIH empieza su ciclo de vida  

E-print Network

VIH debe también ligarse a las proteínas CCR5 ó CXCR4 (co- receptores) para entrar en la célula receptor CD4 glucoproteína del VIH envoltura del VIH CCR5 receptor o CXCR4 receptor Un servicio del

Levin, Judith G.

12

NaF Documentation  

Cancer.gov

The NaF documentation files are presented in Adobe Acrobat or Word files. PDF Generic Documentation for NaF PDF file Word Generic Documentation for NaFWord file Contact Paula M. Jacobs, Ph.D., 301-435-9181, jacobsp@mail.nih.gov, for information. Print

13

Slovenski terminološki sistemi na primeru pravne terminologije  

E-print Network

motivirajo- ?ega pomena omogo?a natan?nost in nedvoumnost motiviranega. 4 Pogodba o Ustavi za Evropo (PUE) Za pravni red ES (acquis communautaire) 1#4; velja na?elo primarnosti, kar pomeni, da »pravna pravila, sprejeta na ravni EU, prevladajo nad pravnimi... tudi PUE postala del pri- marne zakonodaje. Njena priprava je bila napovedana v Izjavi o prihodnosti Unije (Laeken, decem- ber 2001), ki je bila dodana Pogodbi iz Nice. 1#4; V skladu z Laekensko izjavo se je o prihodnosti EU odlo?alo na Konvenciji o...

Fajfar, Tanja

2007-01-01

14

Transitions in Na IIITransitions in Na III  

Microsoft Academic Search

The work of Blackford and Hibbert (1994 At.Data Nucl.Data Tables58 101-64) has been extended to provide oscillator strengths and transition probabilities for J?J' transitions amongst n = 2 and n = 3 levels of Na III. Configuration interaction wavefunctions, obtained with the code CIV3 in the Breit-Pauli approximation, and with additional correlation effects, have been constructed. Further semi-empirical corrections to

D. McPeake; A. Hibbert

2000-01-01

15

Instantánea del cáncer colorrectal  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer colorrectal; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

16

Results from NA57  

E-print Network

The NA57 experiment has measured the production of strange and multi-strange hadrons in heavy-ion collisions at the CERN SPS. After briefly introducing the NA57 apparatus and analysis procedures, we present recent results on strangeness enhancement in Pb-Pb relative to p-Be collisions, on the study of the m_T distributions of strange particles, and on central-to-peripheral nuclear modification factors in Pb-Pb collisions at top SPS energy.

Andrea Dainese

2005-09-30

17

Temas y rumbos del teatro rural hispanoamericano del siglo XX.  

E-print Network

de peculiaridades fonéticas. Son pocos, en realidad, los autores de dramas campesinos que no se han servido del pintoresco lenguaje del campo.1 Algunos autores utilizan fábulas del acervo folklórico para montar piezas de teatro con el fin de...

Neglia, Erminio G.

1971-10-01

18

Na Cauda do Cometa  

NASA Astrophysics Data System (ADS)

Quando viam um cometa, os antigos gregos imaginavam uma estrela com uma vasta cabeleira. Não à toa, a palavra deriva do termo koma, que significa cabelo. Constituídos por fragmentos de gelo e gases, os cometas possuem um núcleo sólido, que pode ter vários quilômetros de diâmetro, e uma cauda que sempre aponta na direção contrária ao Sol, devido aos ventos solares. Graças à aparência de pontos luminosos em movimento (ao contrário de outros astros, que parecem estáticos), esses corpos celestes foram interpretados por diferentes povos com muito misticismo, inspirando mitos tanto de boas-novas como de maus presságios. Conheça algumas dessas histórias:

Voelzke, M. R.

2009-01-01

19

Boletín del Instituto Nacional del Cáncer - 07-20-2010  

Cancer.gov

El doctor Harold Varmus, acompañado de su esposa Constance Casey (centro), presta juramento como director del NCI ante la Secretaria del Departamento de Salud y Servicios Humanos, Kathleen Sebelius, el lunes 12 de julio. (Foto cortesía de Chris Smith) El 12 de julio, el doctor Harold Varmus prestó juramento ante la Secretaria del Departamento de Salud y Servicios Humanos de los Estados Unidos, Kathleen Sebelios, como el decimocuarto director del Instituto Nacional del Cáncer.

20

El pronóstico del cáncer  

Cancer.gov

Hoja informativa sobre la predicción de resultados y recuperación de una enfermedad, y sobre cómo las estadísticas ayudan a los médicos a hacer una estimación del pronóstico de un paciente con cáncer.

21

Control del cáncer y salud mundial: noticia del Instituto Nacional del Cáncer (NCI)  

Cancer.gov

En combinación con una reunión de alto nivel de las Naciones Unidas sobre enfermedades no transmisibles en países en vías de desarrollo, el doctor Harold Varmus, director del NCI, y el doctor Ted L. Trimble, del NCI, han publicado un comentario en Science Translational Medicine sobre “La integración del control del cáncer en la salud mundial" (Integrating Cancer Control into Global Health).

22

Boletín del Instituto Nacional del Cáncer  

Cancer.gov

No se puede negar que vivimos en una comunidad global, en la que los eventos de una ciudad o país pueden tener graves consecuencias para los residentes de otra ciudad o país a miles de kilómetros de distancia. Ya sea la pandemia del virus H1N1, los recientes disturbios en Irán o la recesión económica mundial, es evidente que esta interconectividad trae consigo retos importantes. Pero también puede crear oportunidades sin precedentes, en particular aquellas que podrían mejorar sustancialmente la salud pública.

23

Obesidade infantil: excessos na sociedade  

Microsoft Academic Search

1 Resumo: A obesidade representa um grave problema de saúde pública, caracterizada por um contexto de epidemia mundial. A especificidade da obesidade infantil se estabelece a partir das conseqüências físicas e emocionais da doença, além da elevação dos riscos da moléstia na vida adulta. Através de encontros grupais com familiares de crianças obesas, identificaram-se aspectos relevantes na vida social que

Andréia Mendes dos Santos

24

Museo Universitario del Chopo Datos del plan de estudio  

E-print Network

and roll 4. Mambo 5. Merengue 6. Disco 7. Cumbia 8. Cha cha cha 9. Salsa en Línea 10. Hip Hop 11. CancionesMuseo Universitario del Chopo Datos del plan de estudio Nombre del Taller: Dancing en México

Islas, León

25

Pruebas de Papanicolaou y del virus del papiloma humano (VPH)  

Cancer.gov

Hoja informativa que describe los exámenes selectivos de detección del cáncer de cérvix, los cuales incluyen la prueba de Papanicolaou y la prueba de los virus del papiloma humano. La hoja informativa incluye también información acerca de las pautas de exámenes de detección del cáncer de cérvix.

26

Boletín del Instituto Nacional del Cáncer - 08-17-2010  

Cancer.gov

En la reunión del 20 de julio, los miembros del comité revisaron los resultados finales de esos estudios, en los cuales no se pudo confirmar la información que llevó a la aprobación acelerada. Las mujeres del estudio inicial, llamado E2100, recibieron paclitaxel (Taxol) solo o paclitaxel más bevacizumab para tratar el cáncer de mama localizado recidivante.

27

Instantánea del cáncer de pulmón  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de pulmón; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

28

Instantánea del cáncer de riñón  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de riñón; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

29

Instantánea del cáncer de tiroides  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de tiroides; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

30

Instantánea del cáncer de páncreas  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de páncreas; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

31

Instantánea del cáncer de ovario  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de ovario; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

32

Instantánea del cáncer de endometrio  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de endometrio; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

33

Instantánea del cáncer de próstata  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de próstata; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

34

Instantánea del cáncer de esófago  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de esófago; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

35

Instantánea del cáncer de vejiga  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de vejiga; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

36

Fisiología del crecimiento  

Microsoft Academic Search

ExtractoEl crecimiento humano es un proceso dinámico y complejo que comienza con la fertilización del óvulo y se completa con la fusión de las epífisis y las metáfisis de los huesos largos, que caracteriza la terminación de la adolescencia. El crecimiento ocurre en fases, con características distintivas en términos de influencias dominantes derivadas de factores y patrones genéticos, ambientales\\/nutricionales y

Arlan L. Rosenbloom

2007-01-01

37

Challenges for Na-ion Negative Electrodes  

E-print Network

Na-ion batteries have been proposed as candidates for replacing Li-ion batteries. In this paper we examine the viability of Na-ion negative electrode materials based on Na alloys or hard carbons in terms of volumetric ...

Chevrier, V. L.

38

-DERECHO PBLICO DEL ESTADO AUTONMICO La implantacin del Mster universitario en Derecho Pblico del Estado Autonmico  

E-print Network

- DERECHO P�BLICO DEL ESTADO AUTON�MICO La implantación del Máster universitario en Derecho Público del Estado Autonómico extinguirá el Máster Oficial en Derecho Autonómico y Local. Por esta razón se materias del Máster Oficial en Derecho Autonómico y Local. Los estudiantes que comenzaron el Máster Oficial

Rey Juan Carlos, Universidad

39

Propostes temes del treball sobre ER Treball sobre una font d'energia renovable  

E-print Network

Propostes temes del treball sobre ER Treball sobre una font d'energia renovable Estudi de l'estat de desenvolupament, la implantaci´o i evoluci´o hist`orica d'u- na font d'energia renovable concreta: · Solar fotovoltaica · Solar trmica · Biocombustibiles · Elica Treball sobre una tecnologia espec

Batiste, Oriol

40

Museo Universitario del Chopo Datos del plan de estudio  

E-print Network

separación de la agrupación musical más importante del Siglo XX, a nuestros días, The Beatles Imparte NACIONAL AUT�NOMA DE M�XICO #12;Revisar la historia de la banda de rock los Beatles, a través del análisis paralelos en el tiempo del cuarteto Liverpool. CONTENIDO 1. La historia des los Beatles, desde sus inicios

Islas, León

41

Aceptabilidad del diagn?stico r?pido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires  

PubMed Central

Resumen El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin.

Balan, Ivan C.; Carballo-Dieguez, Alex; Marone, Ruben O.; Pando, Maria A.; Barreda, Victoria; Avila, Maria M.

2011-01-01

42

Determination of the (Na+) Sternheimer antishielding factor by 23Na NMR spectroscopy on sodium oxide chloride, Na3OCl.  

PubMed

The (Na+) Sternheimer antishielding factor gammainifinity (Na+) was determined by 23Na NMR spectroscopy on sodium oxide-chloride, Na3OCl. The quadrupolar coupling constant of the sodium ion in Na3OCI was determined to QCC = 11.34 MHz, which presents the largest coupling constant of a sodium nucleus observed so far. Applying a simple point charge model, the largest principal value of the electric field gradient at the sodium site was calculated to V(zz) = -6.76762 x 10(20) V/m2. From these values we calculated the (Na+) Sternheimer antishielding factor to gammainifinity (Na+)= -5.36. In sodium oxide, Na2O, we observed an isotropic chemical shift of deltaCS = 55.1 ppm, referenced to 1 M aqueous NaCI (delta = 0 ppm). PMID:10928632

Klösters, G; Jansen, M

2000-07-01

43

MÉXICO: DESIGUALDAD SOCIAL Y POBREZA Saldos del “gobierno del empleo”  

Microsoft Academic Search

El gobierno de Felipe Calderón Hinojosa, carente de oficio y de sentido común, no solamente es el gobierno del desempleo sino que también es el gobierno del aumento de las desigualdades sociales y, por tanto, de la pobreza. Y cómo no debería serlo, sí se trata de un gobierno conservador que les quita a los pobres para darles a los

Martín Carlos Ramales Osorio

2010-01-01

44

Boletín del Instituto Nacional del Cáncer - 09-14-2010  

Cancer.gov

Las mediciones ecocardiográficas del ventrículo izquierdo del corazón sirven para que los médicos monitoreen el funcionamiento cardiaco durante el tratamiento contra el cáncer. Una reducción de la fracción de eyección ventricular izquierda (LVEF) durante el tratamiento puede indicar daño cardiaco provocado por los fármacos. Haga clic para ampliar.

45

Original article Soybean impairs Na  

E-print Network

Original article Soybean impairs Na + -dependent glucose absorption and Cl ­ secretion in porcine -- Recent evidence indicates that soybean, which is widely used in animal nutrition, could directly alter of the study was to investigate the effect of three differently treated soybean prod- ucts on the glucose

Boyer, Edmond

46

BREAKFAST MENU (665 MG NA)  

E-print Network

) Garden Vegetable (80 MG) Beef Broth(140 MG) Cottage Cheese (410 MG) Tossed Salad (O MG) (Oil & Vinegar SODIUM (2000 GM NA) COLD ENTREES: Chicken Caesar Salad (440 MG) (Oil & Vinegar/Lowfat Italian EACH) Baked Potato Chips (170 MG) ACCOMPANIMENTS: (Limit 1 Starch 1 Veg) Green Beans(6 MG) Broccoli

Oliver, Douglas L.

47

El valor del consejo en el Libro del caballero Zifar Patricia ROCHWERT-ZUILI  

E-print Network

1 El valor del consejo en el Libro del caballero Zifar Patricia ROCHWERT-ZUILI Textes et cultures Libro del caballero Zifar la definición del consejo como elemento fundamental del molinismo. El análisis la realeza. Palabras clave: Consejo, palabra, amistad, verdad, seso, entendimiento, Libro del

Paris-Sud XI, Université de

48

NA61/SHINE ion program  

E-print Network

The Super Proton Synchrotron (SPS) at CERN covers one of the most interesting regions of the phase diagram (T - \\mu_{B}) of strongly interacting matter. The study of central Pb+Pb collisions by NA49 indicate that the threshold for deconfinement is reached already at the low SPS energies. Theoretical considerations predict a critical point of strongly interacting matter at energies accessible at the SPS. The NA61/SHINE experiment, a successor of the NA49 project, will study hadron production in p+p, p+A, h+A, and A+A reactions at various energies. The broad physics program includes the investigation of the properties of strongly interacting matter, as well as precision measurements of hadron spectra for the T2K neutrino experiment and for the Pierre Auger Observatory and KASCADE cosmic-ray projects. The main physics goals of the NA61/SHINE ion program are to study the properties of the onset of deconfinement at low SPS energies and to find signatures of the critical point of strongly interacting matter. To achieve these goals a broad range in the (T - \\mu_{B}) phase diagram will be covered by performing an energy (10A-158A GeV/c) and system size (p+p, B+C, Ar+Ca, Xe+La) scan. The first data for this 2-D scan were taken in 2009, i.e. p+p interactions at 20, 30, 40, 80, 158 GeV/c beam energy. This contribution will summarize physics arguments for the NA61/SHINE ion program, show the detector performance and present the current status of the experiment and plans for the next years.

Maja Mackowiak for the NA61 Collaboration

2010-09-06

49

EL ORIGEN BIOLÓGICO DEL DERECHO  

Microsoft Academic Search

En este trabajo se aborda el posible origen evolutivo del derecho como una consecuencia del desarrollo social de nuestra especie. Otras especies con sistemas sociales similares presentan varias reglas para la convivencia en grupo. Algunas de estas reglas son comunes en todas las especies con comportamiento social. El desarrollo de la sociobiología en las últimas décadas es una herramienta importante

Axel P. Retana-Salazar

50

Teatro uruguayo hacia el fin del siglo  

E-print Network

del Interior y la Asociación General de Autores del Uruguay, y presidida por un representante del Ministerio de Educación y Cultura. 84 LATIN AMERICAN THEATRE REVIEW Pero los magros recursos asignados al Fondo de Teatro por dicha ley, consistentes...

Pignataro Calero, Jorge

1993-10-01

51

Vacunas contra los virus del papiloma humano  

Cancer.gov

Hoja informativa acerca de las vacunas contra los virus del papiloma humano (VPH) para prevenir infecciones con ciertos tipos de VPH, los cuales son la causa principal del cáncer de cuello del útero o cérvix.

52

Melting of the Na layers in solid Na0.8CoO2.  

PubMed

Data of 23Na NMR spectra and relaxation measurements are interpreted as suggesting that, upon increasing temperature, the Na layers in Na0.8CoO2 adopt a 2D liquid state at T=291 K. The corresponding first order phase transition is preceded by a rapidly increasing mobility and diffusion of Na ions above 200 K. Above 291 K, the 23Na NMR response is similar to that previously observed in superionic conductors with planar Na layers. PMID:19257527

Weller, M; Sacchetti, A; Ott, H R; Mattenberger, K; Batlogg, B

2009-02-01

53

Hypernatremia inhibits NaHCO3 reabsorption and associated NaCl reabsorption in dogs  

Microsoft Academic Search

Hypernatremia inhibits NaHCO3 reabsorption and associated NaCl reabsorption in dogs. To examine the effect of selective rise of plasma NaCl concentration (hypematremia) on NaHCO3 reabsorption and associated NaCl reabsorption remaining during continuous ethacrynic acid infusion, hypertonic NaCl solution was infused in three groups of anesthetized volume-expanded dogs. In six dogs examined at constant hematocrit and plasma pH, bicarbonate and water

Harald Langberg; Anders Hartmann; Jonny Østensen; Øystein Mathisen; Fredrik Kiil

1986-01-01

54

Ionic regulation of Na absorption in proximal colon: cation inhibition of electroneutral Na absorption  

SciTech Connect

Active Na absorption (J/sub net//sup NA/) in rabbit proximal colon in vitro is paradoxically stimulated as (Na) in the bathing media is lowered with constant osmolarity. J/sub m..-->..s//sup Na/ increases almost linearly from 0 to 50 mM (Na)/sub 0/ but then plateaus and actually decreases from 50 to 140 mM (Na)/sub 0/, consistent with inhibition of an active transport process. Both lithium and Na are equally effective inhibitors of J/sub net//sup Na/, whereas choline and mannitol do not block the high rate of J/sub net//sup Na/ observed in decreased (Na)/sub 0/. Either gluconate or proprionate replacement of Cl inhibits J/sub net//sup Na/. J/sub net//sup Na/ at lowered (Na)/sub 0/ is electrically silent and is accompanied by increased Cl absorption; it is inhibited by 10/sup -3/ M amiloride and 10/sup -3/ theophylline but not by 10/sup -4/ M bumetanide. Epinephrine is equally effective at stimulating Na absorption at 50 and 140 mM (Na). Na gradient experiments are consistent with a predominantly serosal effect of the decreased (Na)/sub 0/. These results suggest that 1) Na absorption in rabbit proximal colon in vitro is stimulated by decreased (Na); 2) the effect is cation specific, both Na and Li blocking the stimulatory effect; 3) the transport is mediated by Na-H exchange and is Cl dependent but 4) is under different regulatory mechanisms than the epinephrine-sensitive Na-Cl cotransport previously described in proximal colon. Under the appropriate conditions, proximal colon absorbs Na extremely efficiently. Na-H exchange in this epithelium is cation inhibitable, either directly or by a secondary regulatory process.

Sellin, J.H.; De Soignie, R.

1987-01-01

55

Na+ Tolerance and Na+ Transport in Higher Plants  

PubMed Central

Tolerance to high soil [Na+] involves processes in many different parts of the plant, and is manifested in a wide range of specializations at disparate levels of organization, such as gross morphology, membrane transport, biochemistry and gene transcription. Multiple adaptations to high [Na+] operate concurrently within a particular plant, and mechanisms of tolerance show large taxonomic variation. These mechanisms can occur in all cells within the plant, or can occur in specific cell types, reflecting adaptations at two major levels of organization: those that confer tolerance to individual cells, and those that contribute to tolerance not of cells per se, but of the whole plant. Salt?tolerant cells can contribute to salt tolerance of plants; but we suggest that equally important in a wide range of conditions are processes involving the management of Na+ movements within the plant. These require specific cell types in specific locations within the plant catalysing transport in a coordinated manner. For further understanding of whole plant tolerance, we require more knowledge of cell?specific transport processes and the consequences of manipulation of transporters and signalling elements in specific cell types. PMID:12646496

TESTER, MARK; DAVENPORT, ROMOLA

2003-01-01

56

Na+-stimulated ATPase of alkaliphilic halotolerant cyanobacterium Aphanothece halophytica translocates Na+ into proteoliposomes via Na+ uniport mechanism  

PubMed Central

Background When cells are exposed to high salinity conditions, they develop a mechanism to extrude excess Na+ from cells to maintain the cytoplasmic Na+ concentration. Until now, the ATPase involved in Na+ transport in cyanobacteria has not been characterized. Here, the characterization of ATPase and its role in Na+ transport of alkaliphilic halotolerant Aphanothece halophytica were investigated to understand the survival mechanism of A. halophytica under high salinity conditions. Results The purified enzyme catalyzed the hydrolysis of ATP in the presence of Na+ but not K+, Li+ and Ca2+. The apparent Km values for Na+ and ATP were 2.0 and 1.2 mM, respectively. The enzyme is likely the F1F0-ATPase based on the usual subunit pattern and the protection against N,N'-dicyclohexylcarbodiimide inhibition of ATPase activity by Na+ in a pH-dependent manner. Proteoliposomes reconstituted with the purified enzyme could take up Na+ upon the addition of ATP. The apparent Km values for this uptake were 3.3 and 0.5 mM for Na+ and ATP, respectively. The mechanism of Na+ transport mediated by Na+-stimulated ATPase in A. halophytica was revealed. Using acridine orange as a probe, alkalization of the lumen of proteoliposomes reconstituted with Na+-stimulated ATPase was observed upon the addition of ATP with Na+ but not with K+, Li+ and Ca2+. The Na+- and ATP-dependent alkalization of the proteoliposome lumen was stimulated by carbonyl cyanide m - chlorophenylhydrazone (CCCP) but was inhibited by a permeant anion nitrate. The proteoliposomes showed both ATPase activity and ATP-dependent Na+ uptake activity. The uptake of Na+ was enhanced by CCCP and nitrate. On the other hand, both CCCP and nitrate were shown to dissipate the preformed electric potential generated by Na+-stimulated ATPase of the proteoliposomes. Conclusion The data demonstrate that Na+-stimulated ATPase from A. halophytica, a likely member of F-type ATPase, functions as an electrogenic Na+ pump which transports only Na+ upon hydrolysis of ATP. A secondary event, Na+- and ATP-dependent H+ efflux from proteoliposomes, is driven by the electric potential generated by Na+-stimulated ATPase. PMID:20691102

2010-01-01

57

Phase transitions and equations of state for the sodium halides: NaF NaCl, NaBr, and NaI  

NASA Astrophysics Data System (ADS)

Phase changes and equations of state of four sodium halides, NaF, NaCl, NaBr, and NaI, have been studied up to ˜60 GPa at room temperature with the use of a diamond anvil cell. NaF and NaCl transform from the B1 phase to the B2 phase at ˜23 GPa and ˜29 GPa, respectively. At ˜33 GPa, NaBr transforms from the B1 phase to an unidentified phase with a lower symmetry than the B2 phase. NaI also transforms at ˜32 GPa to a new phase which seems to have the same structure as that of the high-pressure phase of NaBr. The B2 phase of NaF has bulk modulus K0 = 103 (±19) GPa and volume ratio at 1 atm Vo2/Vo1 = 0.811 (±0.025), and the B2 phase of NaCl has K0 = 121 (±23) GPa and V02/V01 = 0.734 (±0.022). The volume change across the transition was estimated to be ?V/V1 ? -10.4% for NaF and -5.8% for NaCl.

Sato-Sorensen, Yosiko

1983-04-01

58

NA  

E-print Network

Information regarding the chemical identity of benzene is located in Table 4-1. Although the term benzol is found in older literature for the commercial product, benzene is the name presently approved by the International Union of Pure and Applied Chemistry (IUPAC), the Chemical Manufacturers Association (CMA), and the American Society for Testing and Materials (ASTM) for the pure product.

unknown authors

59

Aithisg Bhliadhnail Coilltearachd na h-Alba  

E-print Network

Aithisg Bhliadhnail �ghdarras Coilltearachd na h-Alba Lèirmheas Bliadhnail 2007-2008 #12;�ghdarras Coilltearachd na h-Alba Lèirmheas Bliadhnail 2007-08 1 | �ghdarras Coilltearachd na h-Alba Lèirmheas Bliadhnail Leasachadh coimhearsnachd 11 Ruigsinneachd agus slàinte 14 Càileachd na h-àrainneachd 17 Bith-iomadachd 19 Mu

60

Siga adelante: la vida después del tratamiento del cáncer  

Cancer.gov

E-book con consejos para supervivientes de cáncer e información sobre temas relacionados con la vida después del tratamiento, entre ellos, la atención médica de seguimiento, los cambios físicos y emocionales y los cambios en el estilo de vida.

61

Boletín del Instituto Nacional del Cáncer - 05-25-2010  

Cancer.gov

Aproximadamente 41.000 participantes en un estudio en el Reino Unido se sometieron una sola vez a una examen de detección en la parte inferior del colon mediante el uso de un sigmoidoscopio, un instrumento delgado en forma de tubo que se inserta a través del recto para buscar lesiones precancerosas o cancerosas. Este dispositivo también tiene una herramienta para extraer pólipos potencialmente precancerosos.

62

Como Solicitar Los Beneficios del Seguro del Desempleo Transcripcin  

E-print Network

depende en los ingresos que ha ganado en un periodo de 12 meses...esto es lo que se le llama ingresos del éste Segundo...usted puede visitar nuestro sitio de Internet y presentar su solicitud en línea O. Busque el enlace de la "Lista de Verificación" en nuestro sitio del Internet. Púlselo e imprímalo. Al

63

Boletín del Instituto Nacional del Cáncer - 3 de enero 2013  

Cancer.gov

En Estados Unidos nos bombardean con información sobre los exámenes de detección del cáncer. Los comerciales radiales tratan de atraer a la gente a los centros médicos subrayando los beneficios de los exámenes de detección del cáncer de pulmón. Algunos grupos de defensa promueven los exámenes para el cáncer de próstata o de mama. Y los medios enfatizan los beneficios de estas pruebas. Pero mucha gente no entiende la complejidad de estos procedimientos.

64

Antioxidantes y prevención del cáncer  

Cancer.gov

Hoja informativa acerca de los antioxidantes, sustancias que pueden proteger las células del daño causado por moléculas inestables conocidas como radicales libres. El daño de los radicales libres puede resultar en cáncer.

65

Case Study: del Amo Bioventing  

EPA Science Inventory

The attached presentation discusses the fundamentals of bioventing in the vadose zone. The basics of bioventing are presented. The experience to date with the del Amo Superfund Site is presented as a case study....

66

Se da a conocer el plan del Instituto Nacional del Cáncer para acelerar la investigación del cáncer  

Cancer.gov

En la 100va Reunión Anual de la Asociación Estadounidense de Investigación del Cáncer realizada en Denver, el director del Instituto Nacional del Cáncer, doctor John E. Niederhuber, dio a conocer detalles importantes, tales como financiamiento de más subvenciones, creación de una plataforma para atención personalizada del cáncer y un programa acelerado de genética del cáncer que hará avanzar la investigación oncológica en este nuevo ambiente económico.

67

Photoabsorption windows for Na and Na{sub 2}{sup +}  

SciTech Connect

There exist absorption windows (i.e., Cooper-minima) in the photoabsorption cross sections of some atomic systems because of the relative phase shifts between the initial and final state wave functions due to the atomic screening potentials in contrast to the Coulomb potentials. Such window positions are sensitive to the accuracy of the initial and final state wave functions. Using our modified Breit-Pauli R-matrix code, the photoionization cross sections of ground Na are calculated. Our calculated cross sections and minimum position in the low photoelectron energy range (<9 eV) are in excellent agreement with the experimental results. In the high energy range (>9 eV), there is an abnormal bump in the experimental measurements, which is a long-standing experimental puzzle. It is interesting to note that there is also an absorption window in the photoabsorption (i.e., photodissociation) cross sections of Na{sub 2}{sup +}. Such an absorption window provides an answer to the puzzle.

Han Xiaoying [Key Laboratory of Atomic and Molecular Nanosciences of Education Ministry, Department of Physics, Tsinghua University, Beijing 100084 (China); Gao Xiang [Department of Physics, Shanghai Jiao Tong University, Shanghai 200230 (China); Li Jiaming [Department of Physics, Shanghai Jiao Tong University, Shanghai 200230 (China); Key Laboratory of Atomic and Molecular Nanosciences of Education Ministry, Department of Physics, Tsinghua University, Beijing 100084 (China); Voky, Lan; Feautrier, Nicole [LERMA, UMR 8112 du CNRS, Observatoire de Paris, 92915 Meudon Cedex (France)

2006-12-15

68

Na + ,K + ATPase Na + Affinity in Rat Skeletal Muscle Fiber Types  

Microsoft Academic Search

Previous studies in expression systems have found different ion activation of the Na+\\/K+-ATPase isozymes, which suggest that different muscles have different ion affinities. The rate of ATP hydrolysis was used\\u000a to quantify Na+,K+-ATPase activity, and the Na+ affinity of Na+,K+-ATPase was studied in total membranes from rat muscle and purified membranes from muscle with different fiber types. The\\u000a Na+ affinity

Michael Kristensen; Carsten Juel

2010-01-01

69

Harold Varmus investido bajo juramento como 14.º director del Instituto Nacional del Cáncer  

Cancer.gov

Ganador del Premio Nobel, doctor Harold E. Varmus, prestó juramento hoy como 14.º director del Instituto Nacional del Cáncer (NCI).  "Es muy estimulante que estés de regreso con nosotros", dijo la secretaria del Departamento de Salud y Servicios Humanos Kathleen Sebelius en la ceremonia de toma de juramento. “Hoy se abre un nuevo capítulo para el Instituto Nacional del Cáncer”.

70

VIII Encuentro Nacional de Teatro del CLETA  

E-print Network

popular de las "calaveras," poemitas satíricos que se circulan en México por motivo del día dos de noviembre, "Día de los Muertos," destacaron esa noche las "calaças" originales del Llanero Solitito; por ejemplo, la siguiente a propósito del actual... contribuir al fortalecimiento de organizaciones políticas y sociales que contribuyan a la destrucción del sistema de explotación del hombre por el hombre." Durante los diez días que duró el VIII Encuentro, hubo presentaciones tanto en foros cerrados como...

Frischmann, Donald H.

1983-10-01

71

Relationship between intracellular Na+ concentration and reduced Na+ affinity in Na+,K+-ATPase mutants causing neurological disease.  

PubMed

The neurological disorders familial hemiplegic migraine type 2 (FHM2), alternating hemiplegia of childhood (AHC), and rapid-onset dystonia parkinsonism (RDP) are caused by mutations of Na(+),K(+)-ATPase ?2 and ?3 isoforms, expressed in glial and neuronal cells, respectively. Although these disorders are distinct, they overlap in phenotypical presentation. Two Na(+),K(+)-ATPase mutations, extending the C terminus by either 28 residues ("+28" mutation) or an extra tyrosine ("+Y"), are associated with FHM2 and RDP, respectively. We describe here functional consequences of these and other neurological disease mutations as well as an extension of the C terminus only by a single alanine. The dependence of the mutational effects on the specific ? isoform in which the mutation is introduced was furthermore studied. At the cellular level we have characterized the C-terminal extension mutants and other mutants, addressing the question to what extent they cause a change of the intracellular Na(+) and K(+) concentrations ([Na(+)]i and [K(+)]i) in COS cells. C-terminal extension mutants generally showed dramatically reduced Na(+) affinity without disturbance of K(+) binding, as did other RDP mutants. No phosphorylation from ATP was observed for the +28 mutation of ?2 despite a high expression level. A significant rise of [Na(+)]i and reduction of [K(+)]i was detected in cells expressing mutants with reduced Na(+) affinity and did not require a concomitant reduction of the maximal catalytic turnover rate or expression level. Moreover, two mutations that increase Na(+) affinity were found to reduce [Na(+)]i. It is concluded that the Na(+) affinity of the Na(+),K(+)-ATPase is an important determinant of [Na(+)]i. PMID:24356962

Toustrup-Jensen, Mads S; Einholm, Anja P; Schack, Vivien R; Nielsen, Hang N; Holm, Rikke; Sobrido, María-Jesús; Andersen, Jens P; Clausen, Torben; Vilsen, Bente

2014-02-01

72

Boletín del Instituto Nacional del Cáncer - 29 de marzo de 2011  

Cancer.gov

Los artículos originales en inglés se encuentran disponibles en las páginas del NCI Cancer Bulletin. El Boletín es una publicación del Instituto Nacional del Cáncer (NCI), una entidad gubernamental de los Estados Unidos creada en 1937.

73

Boletín del Instituto Nacional del Cáncer - 21 de junio de 2011  

Cancer.gov

Los artículos originales en inglés se encuentran disponibles en las páginas del NCI Cancer Bulletin. El Boletín es una publicación del Instituto Nacional del Cáncer (NCI), una entidad gubernamental de los Estados Unidos creada en 1937.

74

Boletín del Instituto Nacional del Cáncer - 28 de febrero de 2012  

Cancer.gov

Los artículos originales en inglés están disponibles en las páginas del NCI Cancer Bulletin. El Boletín es una publicación del Instituto Nacional del Cáncer (NCI), una entidad gubernamental de los Estados Unidos creada en 1937.

75

Growth of binary organic NLO crystals: m.NA-p.NA and m.NA-CNA system  

NASA Technical Reports Server (NTRS)

Experiments were carried out to grow 3.Nitroaniline (m.NA) crystals doped with 4.Nitroaniline (p.NA) and 2.chloro 4.Nitroaniline (CNA). The measured undercooling for m.NA, p.NA, and CNA were 0.21 tm K, 0.23 tm K, and 0.35 tm K respectively, where tm represents the melting temperature of the pure component. Because of the crystals' large heat of fusion and large undercooling, it was not possible to grow good quality crystals with low thermal gradients. In the conventional two-zone Bridgman furnace we had to raise the temperature of the hot zone above the decomposition temperature of CNA, p.NA, and m.NA to achieve the desired thermal gradient. To avoid decomposition, we used an unconventional Bridgman furnace. Two immiscible liquids, silicone oil and ethylene glycol, were used to build a special two-zone Bridgman furnace. A temperature gradient of 18 K/cm was achieved without exceeding the decomposition temperature of the crystal. The binary crystals, m.NA-p.NA and m.NA-CNA, were grown in centimeter size in this furnace. X-ray and optical characterization showed good optical quality.

Singh, N. B.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.

1993-01-01

76

en el mundo Trasplante del arroz en Madagascar  

E-print Network

Ciencias y Tecnologías del Agua » con la ayuda del Ministerio de Asuntos Extranjeros. África del Norte y internacional MERGUSIE, dedicado al manejo integral del agua en la cuenca vertiente del Merguellil. De éste han tecnologías del agua » del Nepad Los lazos entre el Instituto y el NEPAD (The New Partnership for Africa

77

Evaluation of Fc?RIIIB-NA1/NA2 Polymorphism in Visceral Leishmaniasis  

PubMed Central

Background: Several lines of evidence demonstrating that innate and adaptive immunity play important roles in the defense against visceral leishmaniasis (VL). A polymorphism within the Fc?RIIIB gene can lead to the expression of three variants of NA1, NA2, and the combined one (NA1/NA2) which alters affinity of IgG to its receptor. Objectives: The main aim of this study was to evaluate the Fc?RIIIB-NA1/NA2 polymorphism in the Fc?RIIIB gene of VL patients in comparison to healthy controls. Patients and Methods: In this cross-sectional study, three groups; 54 seropositive patients with clinical presentation of VL (group 1), 104 seropositive patients without clinical presentation (group 2), and 104 healthy controls (group 3) were evaluated with respect to the Fc?RIIIB-NA1/NA2 polymorphism using a PCR-SSP method. The titration of anti-leishmania antibodies was analyzed using an immunoflorescence technique. Results: Our results indicated that polymorphisms within the Fc?RIIIB gene (that lead to the expression of the NA1/NA2 isoforms) are significantly associated with VL. The results demonstrated that the genotype heterozygotic for Fc?RIIIB-NA1/NA2 expression was significantly increased in VL patients, group 1 when compared to groups 2 and 3. Conversely, there is a decrease in homozygous NA1 and NA2 genotypes in VL patients; however, the overall frequency of NA1 and NA2 alleles appear similar across the three cohorts examined. Conclusions: According to our results, it is likely that the increased frequency of the Fc?RIIIB-NA1/NA2 genotype is associated with impaired immune responses against VL and its subsequent clearance from the patient. PMID:24910789

Abasi, Mohammad; Lotfi, Pegah; Bazmani, Ahad; Matini, Mohamad; Hajilooi, Mehrdad

2014-01-01

78

UltraHigh NA Structured Illumination Microscopy  

Microsoft Academic Search

We measure the three-dimensional point-spread function and compare the resolution of three high numerical aperture objectives (NA) in a structured illumination fluorescence microscope using three-dimensional images of single quantum dots. Compared with conventional 1.30 and 1.42 NA objectives, the ultra-high 1.65 NA TIRF objectives offer significantly improved lateral spatial resolution of better than 75 nm using 488 nm excitation.

Michael Beversluis; Stephan Stranick

2007-01-01

79

Modeling Na clusters in Ar matrices  

Microsoft Academic Search

We present a microscopic model for Na clusters embedded in raregas matrices. The valence electrons of the Na cluster are described by time-dependent density-functional theory at the level of the local-density approximation (LDA). Particular attention is paid to the semi-classical picture in terms of Vlasov-LDA. The Na+ ions and Ar atoms are handled as classical particles whereby the Ar atoms

F. Fehrer; M. Mundt; P.-G. Reinhard; E. Suraud

2005-01-01

80

Painful Na-channelopathies: an expanding universe.  

PubMed

The universe of painful Na-channelopathies--human disorders caused by mutations in voltage-gated sodium channels--has recently expanded in three dimensions. We now know that mutations of sodium channels cause not only rare genetic 'model disorders' such as inherited erythromelalgia and channelopathy-associated insensitivity to pain but also common painful neuropathies. We have learned that mutations of NaV1.8, as well as mutations of NaV1.7, can cause painful Na-channelopathies. Moreover, recent studies combining atomic level structural models and pharmacogenomics suggest that the goal of genomically guided pain therapy may not be unrealistic. PMID:23664154

Waxman, Stephen G

2013-07-01

81

Cerebral Na concentration, Na appetite and thirst of sheep: influence of somatostatin and losartan.  

PubMed

Na and water intakes of Na-depleted sheep are influenced by changes in cerebral Na concentration. The effect of intracerebroventricular infusion of somatostatin or losartan, the ANG II type 1 receptor antagonist, on the Na appetite and thirst of Na-depleted sheep during infusions that decrease (intracerebroventricular hypertonic mannitol) or increase (intracerebroventricular or systemic hypertonic NaCl) cerebral Na concentration was investigated. Na intake was increased but water intake was unchanged during intracerebroventricular infusion of hypertonic mannitol. The increased Na appetite caused by intracerebroventricular infusion of hypertonic mannitol was decreased by concurrent intracerebroventricular infusion of either somatostatin or losartan, with somatostatin being most effective. Water intake was increased during intracerebroventricular infusion of hypertonic mannitol and somatostatin. Na intake was decreased and water intake was increased during systemic or intracerebroventricular infusion of hypertonic NaCl. Intracerebroventricular infusion of losartan blocked both (Na and water intake), whereas somatostatin did not influence either of these changes in intake. The results further consolidate a role for somatostatin and ANG II in the central mechanisms controlling Na appetite and thirst of sheep. PMID:11171646

Weisinger, R S; Blair-West, J R; Burns, P; Denton, D A; Purcell, B

2001-03-01

82

Boletín del Instituto Nacional del Cáncer - 04-27-2010  

Cancer.gov

Cada vez es más evidente que los esfuerzos mundiales de salud de mayor éxito dependen no solo del aporte de las mentes más brillantes, sino de la colaboración entre ellas para marcar la diferencia en el escenario global. Este enfoque es el motor impulsor detrás de una asociación excepcional con el NCI, financiada en parte por Susan G.

83

Boletín del Instituto Nacional del Cáncer - 01-05-2010  

Cancer.gov

Al caminar por los pasillos del nuevo centro oncológico integral en la sede de Ciencias Médicas de la Universidad de Puerto Rico (UPR) en San Juan, uno debe mantener los ojos abiertos. La mujer que pasa caminando vigorosamente podría ser la doctora Marcia Roxana Cruz-Correa, y no debe uno perderse la oportunidad de conocerla.

84

EL ROL DEL GNERO DENTRO DEL PROCESO DE APRENDIZAJE COLABORATIVO  

E-print Network

de sexo y la forma en que esto afecta las actividades colaborativas. En el presente trabajo se describen los resultados de un experimento desarrollado con el fin de establecer que la diferencia de sexo]. Varios estudios también han demostrado que las diferencias de sexo en el uso del computador están

Guerrero, Luis

85

modelado y analisis del transporte del herbicida glifosato en una ...  

E-print Network

tools for the study of water and contaminant transport in the unsaturated zone. This paper presents ... Tests were designed to. characterize the ... laboratory and field data. RESUMEN ..... donde t1 2/ es la vida-mitad (half-life) del contaminante. El parámetro t1 2/ .... En Soil Science Society of America Journal, 44, 892-898.

(Tom N. Jagatic)

86

Método de determinación del origen geográfico del polen apícola comercial  

Microsoft Academic Search

Cinco muestras de marcas de polen apícola, que son frecuentes en el comercio regional, han sido estudiadas y su composición po- línica analizada mediante diferentes técnicas con el objetivo de conocer su origen geográfico. Se han usado tres métodos que pueden con- siderarse complementarios: los valores porcentuales del análisis de polen por microscopía óptica, el análisis colorimétrico y el estudio

Pilar de Sá-Otero; Silvia Marcial-Bugarín; Sandra Armesto-Baztán; Emilia Díaz-Losada

2002-01-01

87

Boletín del Instituto Nacional del Cáncer - 12-08-2009  

Cancer.gov

El Instituto Nacional del Cáncer (NCI) recientemente puso a disposición carteles y broches de promoción en español para aumentar la concientización sobre los estudios clínicos. Se pretende que los instrumentos animen la conversación con pacientes de cáncer que pudieran estar interesados en participar en un estudio clínico.

88

Epithelial Na(+) channels are regulated by flow.  

PubMed

Na(+) absorption in the renal cortical collecting duct (CCD) is mediated by apical epithelial Na(+) channels (ENaCs). The CCD is subject to continuous variations in intraluminal flow rate that we speculate alters hydrostatic pressure, membrane stretch, and shear stress. Although ENaCs share limited sequence homology with putative mechanosensitive ion channels in Caenorhabditis elegans, controversy exists as to whether ENaCs are regulated by biomechanical forces. We examined the effect of varying the rate of fluid flow on whole cell Na(+) currents (I(Na)) in oocytes expressing mouse alpha,beta,gamma-ENaC (mENaC) and on net Na(+) absorption in microperfused rabbit CCDs. Oocytes injected with mENaC but not water responded to the initiation of superfusate flow (to 4-6 ml/min) with a reversible threefold stimulation of I(Na) without a change in reversal potential. The increase in I(Na) was variable among oocytes. CCDs responded to a threefold increase in rate of luminal flow with a twofold increase in the rate of net Na(+) absorption. An increase in luminal viscosity achieved by addition of 5% dextran to the luminal perfusate did not alter the rate of net Na(+) absorption, suggesting that shear stress does not influence Na(+) transport in the CCD. In sum, our data suggest that flow stimulation of ENaC activity and Na(+) absorption is mediated by an increase in hydrostatic pressure and/or membrane stretch. We propose that intraluminal flow rate may be an important regulator of channel activity in the CCD. PMID:11352841

Satlin, L M; Sheng, S; Woda, C B; Kleyman, T R

2001-06-01

89

Instantánea del cáncer de cuello uterino  

Cancer.gov

Información sobre las tendencias de incidencia, mortalidad y financiamiento del NCI sobre el cáncer de cuello uterino; así como ejemplos de actividades del NCI y adelantos en la investigación de este tipo de cáncer.

90

Interfering Rydberg wave packets in Na  

Microsoft Academic Search

This paper presents an experimental and theoretical analysis of quantum interference between Rydberg wave packets in Na. Pairs of phase-locked wave packets manipulate the total orbital angular momentum of Na Rydberg atoms. Initially, the wave packet is composed of a superposition of s and d Rydberg series. Exploitation of the difference between the quantum defects of the two series allows

R. E. Carley; E. D. Boléat; R. S. Minns; R. Patel; H. H. Fielding

2005-01-01

91

Microflora patógena del queso blanco \\  

Microsoft Academic Search

Resumen: Resumen: Resumen: Resumen: Resumen: El queso telita, es un queso blanco de pasta cocida que se vende sumergido en suero y es elaborado por pequeños productores en queseras artesanales, ubicadas en varios estados del país. Las deficientes condiciones sanitarias de producción, almacenamiento, transporte y comercialización para este producto, son causas importantes de contaminación con microorganismos entre los que pueden

José Gregorio Márquez

92

MERCADO DEL CAFÉ EN MÉXICO  

Microsoft Academic Search

La producción de café en México ostenta amplia relevancia tanto en el plano económico como social. El trabajo se centra en las características del grano de café que podrían aprovecharse, junto con otras estrategias para incrementar su consumo. Por esta razón se realizó un análisis de las estadísticas de oferta y demanda para el café consumido en el país, en

Gustavo Guerra G; Leoncio Reyes B; Juan Ruiz-Ramírez

2012-01-01

93

Regulation of Na+ fluxes in plants  

PubMed Central

When exposed to salt, every plant takes up Na+ from the environment. Once in the symplast, Na+ is distributed within cells and between different tissues and organs. There it can help to lower the cellular water potential but also exert potentially toxic effects. Control of Na+ fluxes is therefore crucial and indeed, research shows that the divergence between salt tolerant and salt sensitive plants is not due to a variation in transporter types but rather originates in the control of uptake and internal Na+ fluxes. A number of regulatory mechanisms has been identified based on signaling of Ca2+, cyclic nucleotides, reactive oxygen species, hormones, or on transcriptional and post translational changes of gene and protein expression. This review will give an overview of intra- and intercellular movement of Na+ in plants and will summarize our current ideas of how these fluxes are controlled and regulated in the early stages of salt stress.

Maathuis, Frans J. M.; Ahmad, Izhar; Patishtan, Juan

2014-01-01

94

Variabilità interannuale del fi toplancton del Lago di Tovel (Trentino, Italia)  

Microsoft Academic Search

RIASSUNTO - Variabilità interannuale del fi toplancton del Lago di Tovel (Trentino, Italia) - Lo studio del fi toplancton del Lago di Tovel nel periodo 2002-2004 ha avuto come principali obiettivi l'analisi della variabilità interannuale delle dinamiche stagionali nel Bacino Principale e nella Baia Rossa, il confronto tra le associazioni fi toplanctoniche attuali e passate (prima e dopo la scomparsa

Monica TOLOTTI; Dámaso CALLIARI; Flavio CORRADINI

95

Boletín del Instituto Nacional del Cáncer - 4 de enero de 2011  

Cancer.gov

En esta edición especial del Boletín del Instituto Nacional del Cáncer, usted conocerá las diversas formas en que el NCI está apoyando los esfuerzos de colaboración internacional en las áreas de investigación, capacitación, comunicación y demás actividades relacionadas con una mejor comprensión del cáncer y el tratamiento de pacientes con esta enfermedad.

96

Substrate interactions of the electroneutral Na+-coupled inorganic phosphate cotransporter (NaPi-IIc)  

PubMed Central

The SLC34 solute carrier family comprises the electrogenic NaPi-IIa/b and the electroneutral NaPi-IIc, which display Na+ : Pi cotransport stoichiometries of 3 : 1 and 2 : 1, respectively. We previously proposed that NaPi-IIc lacks one of the three Na+ interaction sites hypothesised for the electrogenic isoforms, but, unlike NaPi-IIa/b, its substrate binding order is undetermined. By expressing NaPi-IIc in Xenopus oocytes, isotope influx and efflux assays gave results consistent with Na+ being the first and last substrate to bind. To further investigate substrate interactions, we applied a fluorometry-based technique that uses site-specific labelling with a fluorophore to characterize substrate-induced conformational changes. A novel Cys was introduced in the third extracellular loop of NaPi-IIc that could be labelled with a reporter fluorophore (MTS-TAMRA). Although labelling resulted in suppression of cotransport as previously reported for the electrogenic isoforms, changes in fluorescence were induced by changes in extracellular Na+ concentration in the absence of Pi and by changes in extracellular Pi concentration in presence of Na+. These data, combined with 32P uptake data, also support a binding scheme in which Na+ is the first substrate to interact. Moreover, the apparent Pi affinity from fluorometry agreed with that from 32P uptake, confirming the applicability of the fluorometric technique for kinetic studies of electroneutral carriers. Analysis of the fluorescence data showed that like the electrogenic NaPi-IIb, 2 Na+ ions interact cooperatively with NaPi-IIc before Pi binding, which implies that only one of these is translocated. This result provides compelling evidence that SLC34 proteins share common motifs for substrate interaction and that cotransport and substrate binding stoichiometries are not necessarily equivalent. PMID:19596895

Ghezzi, Chiara; Murer, Heini; Forster, Ian C

2009-01-01

97

ECONOMIA, VALORIZZAZIONE, GESTIONE DEL PATRIMONIO TURISTICO  

E-print Network

ECONOMIA, VALORIZZAZIONE, GESTIONE DEL PATRIMONIO TURISTICO Giovedì 23 Giugno 2011 Giovedì23 Giugno 2011 ore 09.00 Presentazione del corso di laurea Aula A Facoltà di Economia UNIVERSITA'DEGLI STUDI DI SALERNO #12;Il corso di laurea interateneo, Economia, Valorizzazione, Gestione del Patrimonio Turistico

Costagliola, Gennaro

98

On the formation of transient (Na19)2 and (Na20)2 cluster dimers from molecular dynamics simulations  

Microsoft Academic Search

By using distance-dependent tight-binding molecular dynamics simulations, we discuss the possibilities to form (Na19)2 and (Na20)2 cluster dimers in sodium cluster-cluster collisions. In the case of Na19+Na19, we show that the formation of a prolate dimer-like (Na19)2 may depend on the initial relative orientations of the colliding clusters. A similar study for Na20+Na20 does not seen to show the same

F. S. Zhang; F. Spiegelmann; E. Suraud; V. Frayssé; R. Poteau; R. Glowinski; F. Chatelin

1994-01-01

99

Polarization dependence of Na/emph>+Na/emph> associative ionization revisited  

NASA Astrophysics Data System (ADS)

The dependence of the associative ionization process Na 3 2P3/2+Na 3 2P3/2-->Na2 ++e- on the polarization of the laser light used for Na excitation was independently investigated in Utrecht and Berlin. The purpose of this paper is to clarify discrepancies between earlier experimental results of Kircz, Morgenstern, and Nienhuis, on one hand, and Rothe, Theyunni, Reck, and Tung on the other hand. The new results confirm in general the data of Kircz, Morgenstern, and Nienhuis, and also indicate a dependence of the anisotropy ratios on the relative velocity of the interacting Na* atoms.

Meijer, H. A. J.; Meulen, H. P. V. D.; Morgenstern, R.; Hertel, I. V.; Meyer, E.; Schmidt, H.; Witte, R.

1986-02-01

100

Uso del Los SIG en ModelosUso del Los SIG en ModelosUso del Los SIG en Modelos Hidrolgicos y de Calida de Agua  

E-print Network

Calida de Agua Uso del Los SIG en Modelos Hidrol�gicos y de Calida de Agua (Caso de Uso Cuenca del Ri Luis R. P�rez-Alegr�a PhD P.E.Luis R. P�rez-Alegr�a PhD P.E. #12;Usos del AguaUsos del AguaUsos del AguaUsos del Agua Navegaci�n Consumo Humano HigieneHigiene PescaRecreaci�n #12;Calidad del Agua

Gilbes, Fernando

101

Race and sex differences in erythrocyte Na+, K+, and Na+-K+-adenosine triphosphatase.  

PubMed Central

Several reports indicate that erythrocytes (RBCs) from blacks and men have higher sodium concentrations than those from whites and women. One possible mechanism to explain this finding is a difference in the activity of Na+-K+-ATPase. To explore this possibility, we have studied the Na+ and K+ kinetics of RBC Na+-K+-ATPase and RBC Na+ and K+ concentrations in 37 normotensive blacks and whites, both males and females. The maximal initial reaction velocity (Vmax) values for RBC Na+-K+-ATPase were lower in blacks and men as compared with whites and women. Higher RBC Na+ levels were observed in blacks and males vs. whites and females. Significant inverse correlations were noted between the Na+-K+-ATPase activity and RBC Na+ concentrations. These findings indicate that cellular Na+ homeostasis is different in blacks and men as compared with whites and women. Since higher RBC Na+ concentrations have also been observed in patients with essential hypertension as compared with normotensive subjects, the higher intracellular Na+ concentrations in blacks and men may contribute to the greater predisposition of these groups to essential hypertension. PMID:2989333

Lasker, N; Hopp, L; Grossman, S; Bamforth, R; Aviv, A

1985-01-01

102

Cytosolic Na+ Controls an Epithelial Na+ Channel Via the Go Guanine Nucleotide-Binding Regulatory Protein  

NASA Astrophysics Data System (ADS)

In tight Na+-absorbing epithelial cells, the rate of Na+ entry through amiloride-sensitive apical membrane Na+ channels is matched to basolateral Na+ extrusion so that cell Na+ concentration and volume remain steady. Control of this process by regulation of apical Na+ channels has been attributed to changes in cytosolic Ca2+ concentration or pH, secondary to changes in cytosolic Na+ concentration, although cytosolic Cl- seems also to be involved. Using mouse mandibular gland duct cells, we now demonstrate that increasing cytosolic Na+ concentration inhibits apical Na+ channels independent of changes in cytosolic Ca2+, pH, or Cl-, and the effect is blocked by GDP-? -S, pertussis toxin, and antibodies against the ? -subunits of guanine nucleotide-binding regulatory proteins (Go). In contrast, the inhibitory effect of cytosolic anions is blocked by antibodies to inhibitory guanine nucleotide-binding regulatory proteins (Gi1/Gi2. It thus appears that apical Na+ channels are regulated by Go and Gi proteins, the activities of which are controlled, respectively, by cytosolic Na+ and Cl-.

Komwatana, P.; Dinudom, A.; Young, J. A.; Cook, D. I.

1996-07-01

103

MSTER UNIVERSITARIO EN DIRECCIN INTERNACIONAL DEL TURISMO HORARIOS DEL CURSO 2014-2015 CAMPUS DE FUENLABRADA  

E-print Network

:00 19:00-20:00 Economía del turismo internacional: impactos y modelos Sistemas y Tecnología Economía del turismo internacional: impactos y modelos Sistemas y Tecnología Economía del turismo internacional:00-20:00 Economía del turismo internacional: impactos y modelos Sistemas y Tecnología Economía del turismo

Rey Juan Carlos, Universidad

104

Boletín del Instituto Nacional del Cáncer - 03-02-2010  

Cancer.gov

Algunas mujeres con cáncer de ovarios reportan síntomas que incluyen dolor abdominal, meteorismo y sensación de llenura antes de que haya un diagnóstico. Pero un estudio nuevo concluye que vigilar estos síntomas relativamente inespecíficos en las mujeres tendría un valor limitado en la detección de la enfermedad. Los médicos tendrían que evaluar a 100 mujeres con estos síntomas para encontrar un cáncer de ovarios, informaron los investigadores en Internet en la revista Journal of the National Cancer Institute del 28 de enero.

105

Gasotransmitters: Novel Regulators of Epithelial Na+ Transport?  

PubMed Central

The vectorial transport of Na+ across epithelia is crucial for the maintenance of Na+ and water homeostasis in organs such as the kidneys, lung, or intestine. Dysregulated Na+ transport processes are associated with various human diseases such as hypertension, the salt-wasting syndrome pseudohypoaldosteronism type 1, pulmonary edema, cystic fibrosis, or intestinal disorders, which indicate that a precise regulation of epithelial Na+ transport is essential. Novel regulatory signaling molecules are gasotransmitters. There are currently three known gasotransmitters: nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S). These molecules are endogenously produced in mammalian cells by specific enzymes and have been shown to regulate various physiological processes. There is a growing body of evidence which indicates that gasotransmitters may also regulate Na+ transport across epithelia. This review will summarize the available data concerning NO, CO, and H2S dependent regulation of epithelial Na+ transport processes and will discuss whether or not these mediators can be considered as true physiological regulators of epithelial Na+ transport biology. PMID:22509167

Althaus, Mike

2012-01-01

106

Gasotransmitters: novel regulators of epithelial na(+) transport?  

PubMed

The vectorial transport of Na(+) across epithelia is crucial for the maintenance of Na(+) and water homeostasis in organs such as the kidneys, lung, or intestine. Dysregulated Na(+) transport processes are associated with various human diseases such as hypertension, the salt-wasting syndrome pseudohypoaldosteronism type 1, pulmonary edema, cystic fibrosis, or intestinal disorders, which indicate that a precise regulation of epithelial Na(+) transport is essential. Novel regulatory signaling molecules are gasotransmitters. There are currently three known gasotransmitters: nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H(2)S). These molecules are endogenously produced in mammalian cells by specific enzymes and have been shown to regulate various physiological processes. There is a growing body of evidence which indicates that gasotransmitters may also regulate Na(+) transport across epithelia. This review will summarize the available data concerning NO, CO, and H(2)S dependent regulation of epithelial Na(+) transport processes and will discuss whether or not these mediators can be considered as true physiological regulators of epithelial Na(+) transport biology. PMID:22509167

Althaus, Mike

2012-01-01

107

The voltage-gated Na channel NaVBP has a role in motility, chemotaxis, and pH homeostasis  

E-print Network

The voltage-gated Na channel NaVBP has a role in motility, chemotaxis, and pH homeostasis, is a voltage-gated Na channel potentiated by alkaline pH. NaVBP has roles in motility, chemotaxis, and pH homeostasis at high pH. Reduced motility of bacteria lacking functional NaVBP was reversed by restoration

Clapham, David E.

108

Malattie cistiche del parenchima renale  

Microsoft Academic Search

\\u000a La malattia cistica del parenchima renale rappresenta un eterogeneo gruppo di malattie a carattere congenito, ereditario e\\u000a non, e acquisito caratterizzate dalla presenza di formazioni cistiche. Il riscontro di formazioni cistiche renali è molto\\u000a frequente nella pratica clinica quotidiana. Solo un’adeguata conoscenza degli aspetti anatomopatologici permette la giusta\\u000a comprensione delle manifestazioni cliniche e la corretta interpretazione dei reperti radiologici. Compito

Fulvio Stacul; Marco F. Cavallaro; Maria A. Cova

109

Lecciones del de comerciode la  

E-print Network

Udios china-méxico © 2011 Por características tipográficas y de diseño editorial miGUel ÁnGel porrúa, librero Estudios del Desarrollo Universidad nacional aUtónoma de méxico, Centro de Estudios China-México t Desarrollo Económico y Social (Brasil) cafta: Tratado de Libre Comercio de Centro América (Republica

Tufts University

110

Recensin del libro: Modelos Matemticos  

E-print Network

Recensión del libro: Modelos Matemáticos Rafael Ortega Ríos (Aparecerá en la Revista Española de Física) Este libro, breve, elegante y lleno de buen gusto matemático, me parece muy recomendable para de aplicación; cuanto se necesita está claramente expuesto en el mismo libro. Hay cuatro capítulos

Sanz-Serna , J M

111

Catalysis of Na+ permeation in the bacterial sodium channel Na(V)Ab.  

PubMed

Determination of a high-resolution 3D structure of voltage-gated sodium channel Na(V)Ab opens the way to elucidating the mechanism of ion conductance and selectivity. To examine permeation of Na(+) through the selectivity filter of the channel, we performed large-scale molecular dynamics simulations of Na(V)Ab in an explicit, hydrated lipid bilayer at 0 mV in 150 mM NaCl, for a total simulation time of 21.6 ?s. Although the cytoplasmic end of the pore is closed, reversible influx and efflux of Na(+) through the selectivity filter occurred spontaneously during simulations, leading to equilibrium movement of Na(+) between the extracellular medium and the central cavity of the channel. Analysis of Na(+) dynamics reveals a knock-on mechanism of ion permeation characterized by alternating occupancy of the channel by 2 and 3 Na(+) ions, with a computed rate of translocation of (6 ± 1) × 10(6) ions?s(-1) that is consistent with expectations from electrophysiological studies. The binding of Na(+) is intimately coupled to conformational isomerization of the four E177 side chains lining the extracellular end of the selectivity filter. The reciprocal coordination of variable numbers of Na(+) ions and carboxylate groups leads to their condensation into ionic clusters of variable charge and spatial arrangement. Structural fluctuations of these ionic clusters result in a myriad of ion binding modes and foster a highly degenerate, liquid-like energy landscape propitious to Na(+) diffusion. By stabilizing multiple ionic occupancy states while helping Na(+) ions diffuse within the selectivity filter, the conformational flexibility of E177 side chains underpins the knock-on mechanism of Na(+) permeation. PMID:23803856

Chakrabarti, Nilmadhab; Ing, Christopher; Payandeh, Jian; Zheng, Ning; Catterall, William A; Pomès, Régis

2013-07-01

112

Catalysis of Na+ permeation in the bacterial sodium channel NaVAb  

PubMed Central

Determination of a high-resolution 3D structure of voltage-gated sodium channel NaVAb opens the way to elucidating the mechanism of ion conductance and selectivity. To examine permeation of Na+ through the selectivity filter of the channel, we performed large-scale molecular dynamics simulations of NaVAb in an explicit, hydrated lipid bilayer at 0 mV in 150 mM NaCl, for a total simulation time of 21.6 ?s. Although the cytoplasmic end of the pore is closed, reversible influx and efflux of Na+ through the selectivity filter occurred spontaneously during simulations, leading to equilibrium movement of Na+ between the extracellular medium and the central cavity of the channel. Analysis of Na+ dynamics reveals a knock-on mechanism of ion permeation characterized by alternating occupancy of the channel by 2 and 3 Na+ ions, with a computed rate of translocation of (6 ± 1) × 106 ions?s?1 that is consistent with expectations from electrophysiological studies. The binding of Na+ is intimately coupled to conformational isomerization of the four E177 side chains lining the extracellular end of the selectivity filter. The reciprocal coordination of variable numbers of Na+ ions and carboxylate groups leads to their condensation into ionic clusters of variable charge and spatial arrangement. Structural fluctuations of these ionic clusters result in a myriad of ion binding modes and foster a highly degenerate, liquid-like energy landscape propitious to Na+ diffusion. By stabilizing multiple ionic occupancy states while helping Na+ ions diffuse within the selectivity filter, the conformational flexibility of E177 side chains underpins the knock-on mechanism of Na+ permeation. PMID:23803856

Chakrabarti, Nilmadhab; Ing, Christopher; Payandeh, Jian; Zheng, Ning; Catterall, William A.; Pomes, Regis

2013-01-01

113

Rastafari : identidade e hibridismo cultural na Jamaica, 1930-1981.  

E-print Network

??Tese(doutorado)—Universidade de Brasília/Departamento de História, 2006. Na Jamaica, o passado colonial baseado na plantation escravista, produziu uma sociedade estratificada na qual a cor mais clara… (more)

Rabelo, Danilo

2006-01-01

114

Natural Variants of AtHKT1 Enhance Na+ Accumulation in Two Wild Populations of Arabidopsis  

PubMed Central

Plants are sessile and therefore have developed mechanisms to adapt to their environment, including the soil mineral nutrient composition. Ionomics is a developing functional genomic strategy designed to rapidly identify the genes and gene networks involved in regulating how plants acquire and accumulate these mineral nutrients from the soil. Here, we report on the coupling of high-throughput elemental profiling of shoot tissue from various Arabidopsis accessions with DNA microarray-based bulk segregant analysis and reverse genetics, for the rapid identification of genes from wild populations of Arabidopsis that are involved in regulating how plants acquire and accumulate Na+ from the soil. Elemental profiling of shoot tissue from 12 different Arabidopsis accessions revealed that two coastal populations of Arabidopsis collected from Tossa del Mar, Spain, and Tsu, Japan (Ts-1 and Tsu-1, respectively), accumulate higher shoot levels of Na+ than do Col-0 and other accessions. We identify AtHKT1, known to encode a Na+ transporter, as being the causal locus driving elevated shoot Na+ in both Ts-1 and Tsu-1. Furthermore, we establish that a deletion in a tandem repeat sequence approximately 5 kb upstream of AtHKT1 is responsible for the reduced root expression of AtHKT1 observed in these accessions. Reciprocal grafting experiments establish that this loss of AtHKT1 expression in roots is responsible for elevated shoot Na+. Interestingly, and in contrast to the hkt1–1 null mutant, under NaCl stress conditions, this novel AtHKT1 allele not only does not confer NaCl sensitivity but also cosegregates with elevated NaCl tolerance. We also present all our elemental profiling data in a new open access ionomics database, the Purdue Ionomics Information Management System (PiiMS; http://www.purdue.edu/dp/ionomics). Using DNA microarray-based genotyping has allowed us to rapidly identify AtHKT1 as the casual locus driving the natural variation in shoot Na+ accumulation we observed in Ts-1 and Tsu-1. Such an approach overcomes the limitations imposed by a lack of established genetic markers in most Arabidopsis accessions and opens up a vast and tractable source of natural variation for the identification of gene function not only in ionomics but also in many other biological processes. PMID:17140289

Rus, Ana; Baxter, Ivan; Muthukumar, Balasubramaniam; Gustin, Jeff; Lahner, Brett; Yakubova, Elena; Salt, David E

2006-01-01

115

An Update on NA50 and LUCIFER  

E-print Network

Recent analysis of both new (1998) and old (1995,1996) data obtained by the NA50 Collaboration on J/Psi suppression in Pb+Pb are examined in light of our already existing calculations with the relativistic heavy ion simulation LUCIFER. In particular we comment on the unexplained change of transverse energy scale by NA50 and the apparent disappearance from the data of discontinuities in the suppression with transverse energy.

D. E. Kahana; S. H. Kahana

1999-08-20

116

An Update on NA50 and LUCIFER  

E-print Network

Recent analysis of both new (1998) and old (1995,1996) data obtained by the NA50 Collaboration on J/Psi suppression in Pb+Pb are examined in light of our already existing calculations with the relativistic heavy ion simulation LUCIFER. In particular we comment on the unexplained change of transverse energy scale by NA50 and the apparent disappearance from the data of discontinuities in the suppression with transverse energy.

Kahana, D E

1999-01-01

117

Kako natan?na je lahko transkripcija  

E-print Network

analysis. Ur. Deborah Schiffrin, Deborah Tannen, Heidi E. Hamilton. Oxford: Blackwell. 321–348. Michael Alexander Kirkwood HALLIDAY, 1998: An Introduction To Functional Grammar. 6th impression. London. 292–308. Klaus von HEUSINGER, 1999: Intonation... 2000. 6 Glej dalje zgled mh mh mh. — 163 — Kako natan?na je lahko transkripcija Tak je na primer Hallidayev pristop (Halliday 1998: 292–308) k pojmovanju intonacije oz. tonskega poteka, ki je predmet avtorjevih raziskav poleg ritma in tona. Za...

Ivi?, Mira Krajnc

2010-02-01

118

Electrogenic Na +\\/Ca 2+-exchange of nerve and muscle cells  

Microsoft Academic Search

The plasma membrane Na+\\/Ca2+-exchanger is a bi-directional electrogenic (3Na+:1Ca2+) and voltage-sensitive ion transport mechanism, which is mainly responsible for Ca2+-extrusion. The Na+-gradient, required for normal mode operation, is created by the Na+-pump, which is also electrogenic (3Na+:2K+) and voltage-sensitive. The Na+\\/Ca2+-exchanger operational modes are very similar to those of the Na+-pump, except that the uncoupled flux (Na+-influx or -efflux?) is

Tamás L. Török

2007-01-01

119

Vibrational signatures of sodiated oligopeptides (GG-Na+, GGG-Na+, AA-Na+ and AAA-Na+) in the gas phase  

NASA Astrophysics Data System (ADS)

The structures of the sodium complexes of oligoglycines (GG-Na+, GGG-Na+) and oligoalanines (AA-Na+, AAA-Na+) have been studied by infrared spectroscopy in the gas phase. Two different experimental set-ups have been used to generate, trap and analyze the ions. In the first, the complexes were generated by MALDI and analyzed in the cell of a home built FT-ICR mass spectrometer. In the second an external electrospray source was coupled to a Paul type ion trap. Following their trapping, the ions are irradiated in both cases with intense, tunable infrared light in the 1000-2000 cm-1 range, leading to sodium ion detachment and ion fragmentation via the absorption of multiple photons. The resulting experimental spectra are compared to theoretical linear absorption spectra to assign structures. In agreement with calculations, peptide attachment to Na+ is found to have a strong structuring effect: the lowest energy structures involve binding of all carbonyl oxygens to the cation. Detailed comparison of experimental and computed spectra shows that the IRMPD spectroscopy of such gaseous ions allows the differentiation between structures which do not have the same number of carbonyl oxygens bound to Na+, and structures in which the peptide is either wrapped around the ion or capped by it.

Balaj, O. P.; Kapota, C.; Lemaire, J.; Ohanessian, G.

2008-02-01

120

Modeling Na clusters in Ar matrices  

E-print Network

We present a microscopic model for Na clusters embedded in raregas matrices. The valence electrons of the Na cluster are described by time-dependent density-functional theory at the level of the local-density approximation (LDA). Particular attention is paid to the semi-classical picture in terms of Vlasov-LDA. The Na ions and Argon atoms are handled as classical particles whereby the Ar atoms carry two degrees of freedom, position and dipole polarization. The interaction between Na ions and electrons is mediated through local pseudo-potentials. The coupling to the Ar atoms is described by (long-range) polarization potentials and (short-range) repulsive cores. The ingredients are taken from elsewhere developed standards. A final fine-tuning is performed using the NaAr molecule as benchmark. The model is then applied to embedded systems Na8ArN. By close comparison with quantum-mechanical results, we explore the capability of the Vlasov-LDA to describe such embedded clusters. We show that one can obtain a reaso...

Fehrer, F; Reinhard, P G; Suraud, E

2005-01-01

121

Modeling Na clusters in Ar matrices  

NASA Astrophysics Data System (ADS)

We present a microscopic model for Na clusters embedded in raregas matrices. The valence electrons of the Na cluster are described by time-dependent density-functional theory at the level of the local-density approximation (LDA). Particular attention is paid to the semi-classical picture in terms of Vlasov-LDA. The Na+ ions and Ar atoms are handled as classical particles whereby the Ar atoms carry two degrees of freedom, position and dipole polarization. The interaction between Na+ ions and electrons is mediated through local pseudo-potentials. The coupling to the Ar atoms is described by (long-range) polarization potentials and (short-range) repulsive cores. The ingredients are taken from elsewhere developed standards. A final fine-tuning is performed using the NaAr molecule as benchmark. The model is then applied to embedded systems Na8ArN. By close comparison with quantum-mechanical results, we explore the capability of the Vlasov-LDA to describe such embedded clusters. We show that one can obtain a reasonable description by appropriate adjustments in the fine-tuning phase of the model.

Fehrer, F.; Mundt, M.; Reinhard, P.-G.; Suraud, E.

2005-07-01

122

Deliquescence of NaCl-NaNO3, KNO3-NaNO3, and NaCl-KNO3 Salt Mixtures From 90 to 120?C  

SciTech Connect

We conducted reversed deliquescence experiments in saturated NaCl-NaNO{sub 3}-H{sub 2}O, KNO{sub 3}-NaNO{sub 3}-H{sub 2}O, and NaCl-KNO{sub 3}-H{sub 2}O systems from 90 to 120 C as a function of relative humidity and solution composition. NaCl, NaNO{sub 3}, and KNO{sub 3} represent members of dust salt assemblages that are likely to deliquesce and form concentrated brines on high-level radioactive waste package surfaces in a repository environment at Yucca Mountain, NV, USA. Discrepancy between model prediction and experimental code can be as high as 8% for relative humidity and 50% for dissolved ion concentration. The discrepancy is attributed primarily to the use of 25 C models for Cl-NO{sub 3} and K-NO{sub 3} ion interactions in the current Yucca Mountain Project high-temperature Pitzer model to describe the non-ideal behavior of these highly concentrated solutions.

Carroll, S A; Craig, L; Wolery, T J

2004-10-20

123

L'avifauna del Laghetto del Frassino (Peschiera del Garda, Verona, Veneto)  

Microsoft Academic Search

Ten years of ornithological research at Lake Frassino (located near Peschiera del Garda, Verona, Italy) have produced a check-list of the birds dwelling at this Site of Community Importance (S.I.C.) to be produced. Our surveys have revealed that this water basin where ducks stop al- most exclusively during the day represents, together with nearby Lake Garda, the most important wintering

MARCO MORBIOLI; MAURIZIO SIGHELE

124

Determination of Na 2O from sodium aluminate NaAlO 2  

Microsoft Academic Search

The aim of the work was to find a suitable method and conditions for determining Na2O wt.% from NaAlO2. Problems were encountered while titrating NaAlO2 with hydrochloric acid. The problematic area was the pH range 4–10 where aluminum precipitates as hydroxides. The different species of the aluminate solution were determined using potentiometric and complexometric titrations. The equivalent point of the

Teemu Näykki; Anttila Raimo; Perämäki Paavo; Kurikka Antero; Nikula Päivi

2000-01-01

125

Na+, K+, and Cl- transport in resting pancreatic acinar cells  

PubMed Central

To understand the role of Na+, K+, and Cl- transporters in fluid and electrolyte secretion by pancreatic acinar cells, we studied the relationship between them in resting and stimulated cells. Measurements of [Cl-]i in resting cells showed that in HCO3(-)-buffered medium [Cl- ]i and Cl- fluxes are dominated by the Cl-/HCO3- exchanger. In the absence of HCO3-, [Cl-]i is regulated by NaCl and NaK2Cl cotransport systems. Measurements of [Na+]i showed that the Na(+)-coupled Cl- transporters contributed to the regulation of [Na+]i, but the major Na+ influx pathway in resting pancreatic acinar cells is the Na+/H+ exchanger. 86Rb influx measurements revealed that > 95% of K+ influx is mediated by the Na+ pump and the NaK2Cl cotransporter. In resting cells, the two transporters appear to be coupled through [K+]i in that inhibition of either transporter had small effect on 86Rb uptake, but inhibition of both transporters largely prevented 86Rb uptake. Another form of coupling occurs between the Na+ influx transporters and the Na+ pump. Thus, inhibition of NaK2Cl cotransport increased Na+ influx by the Na+/H+ exchanger to fuel the Na+ pump. Similarly, inhibition of Na+/H+ exchange increased the activity of the NaK2Cl cotransporter. The combined measurements of [Na+]i and 86Rb influx indicate that the Na+/H+ exchanger contributes twice more than the NaK2Cl cotransporter and three times more than the NaCl cotransporter and a tetraethylammonium-sensitive channel to Na+ influx in resting cells. These findings were used to develop a model for the relationship between the transporters in resting pancreatic acinar cells. PMID:8786358

1995-01-01

126

FXYD Proteins Stabilize Na,K-ATPase  

PubMed Central

FXYD proteins are a family of seven small regulatory proteins, expressed in a tissue-specific manner, that associate with Na,K-ATPase as subsidiary subunits and modulate kinetic properties. This study describes an additional property of FXYD proteins as stabilizers of Na,K-ATPase. FXYD1 (phospholemman), FXYD2 (? subunit), and FXYD4 (CHIF) have been expressed in Escherichia coli and purified. These FXYD proteins associate spontaneously in vitro with detergent-soluble purified recombinant human Na,K-ATPase (?1?1) to form ?1?1FXYD complexes. Compared with the control (?1?1), all three FXYD proteins strongly protect Na,K-ATPase activity against inactivation by heating or excess detergent (C12E8), with effectiveness FXYD1 > FXYD2 ? FXYD4. Heating also inactivates E1 ? E2 conformational changes and cation occlusion, and FXYD1 protects strongly. Incubation of ?1?1 or ?1?1FXYD complexes with guanidinium chloride (up to 6 m) causes protein unfolding, detected by changes in protein fluorescence, but FXYD proteins do not protect. Thus, general protein denaturation is not the cause of thermally mediated or detergent-mediated inactivation. By contrast, the experiments show that displacement of specifically bound phosphatidylserine is the primary cause of thermally mediated or detergent-mediated inactivation, and FXYD proteins stabilize phosphatidylserine-Na,K-ATPase interactions. Phosphatidylserine probably binds near trans-membrane segments M9 of the ? subunit and the FXYD protein, which are in proximity. FXYD1, FXYD2, and FXYD4 co-expressed in HeLa cells with rat ?1 protect strongly against thermal inactivation. Stabilization of Na,K-ATPase by three FXYD proteins in a mammalian cell membrane, as well the purified recombinant Na,K-ATPase, suggests that stabilization is a general property of FXYD proteins, consistent with a significant biological function. PMID:21228272

Mishra, Neeraj Kumar; Peleg, Yoav; Cirri, Erica; Belogus, Talya; Lifshitz, Yael; Voelker, Dennis R.; Apell, Hans-Juergen; Garty, Haim; Karlish, Steven J. D.

2011-01-01

127

Dr. Matas Alvarado (CV breve) Investigador Titular del Departamento de Computacin del CINVESTAV, Miembro Regular de  

E-print Network

Dr. Mat�as Alvarado (CV breve) Investigador Titular del Departamento de Computaci�n del CINVESTAV� Mat�as Alvarado Mentado Curriculum Vitae CURRENT POSITION Research Scientist (Investigador CINVESTAV 3

Alvarado, Matías

128

Reconstitution of intestinal Na(+)-phosphate cotransporter.  

PubMed

The rabbit intestinal brush-border membrane Na(+)-phosphate cotransporter was purified from sodium dodecyl sulfate (SDS)-brush-border membrane vesicles (BBMV) protein (SDS-treated Ca(2+)-precipitated BBMV) by a three-column chromatography protocol. The purification included a preparative scale chromatofocusing chromatography column over the pH range from 7.4 to 4 after solubilization in 3-[(3-cholamidopropyl)-diamethylammonia]-1-propanesulfonate (CHAPS), a chromatofocusing column over the pH range from 5.6 to 4 after solubilization in n-octyl glucoside, and gel filtration chromatography on a Sephacryl S-200 column. Verification of Na(+)-phosphate cotransporter purification involved substrate affinities, substrate stoichiometry, and inhibitor sensitivity after proteoliposome reconstitution and SDS-polyacrylamide gel electrophoresis (PAGE). After gel filtration Na(+)-dependent phosphate uptake was 3,300-fold enriched compared with the cell homogenate. A single 130-kDa polypeptide was visualized by SDS-PAGE under reducing conditions using silver stain. The coenrichment of this 130-kDa polypeptide and proteoliposome reconstituted Na(+)-dependent phosphate uptake suggest that the intestinal brush-border membrane Na(+)-phosphate cotransporter has been purified and proteoliposome reconstituted. PMID:8476048

Peerce, B E; Cedilote, M; Seifert, S; Levine, R; Kiesling, C; Clarke, R D

1993-04-01

129

Turismo de masas y transporte: el gran reto del turismo del siglo XXI  

Microsoft Academic Search

El turismo masas es una de las grandes consecuciones del estado del bienestar, al tiempo que ha venido generando una actividad económica importante. En este contexto, el turismo internacional aumentó un 50 por ciento en los años noventa. Es cierto que la tecnología ha avanzado mucho para evitar los impactos que esta movilidad genera, si bien el aumento del turismo

José Ángel Hernández Luis

2008-01-01

130

Brief Communications Inwardly Permeating Na Ions Generate the Voltage  

E-print Network

Brief Communications Inwardly Permeating Na Ions Generate the Voltage Dependence of Resurgent Na measured voltage-clamped currents in different Na gradients to test the role of permeating ionsNaionsoccupyingtheexternalpore.Thelackofvoltagesensitivityoftheblockingproteinsuggeststhattheblocker'sbinding site lies outside the membrane field, in the permeation pathway. Introduction Resurgent Na current

Raman, Indira M.

131

Interpretation of the photoelectron spectra of superalkali species: Na3O and Na3O-  

NASA Astrophysics Data System (ADS)

Recently measured photoelectron spectra of the Na3O- anion have been interpreted with the aid of ab initio electron propagator calculations. As in the case of the Li3O-, we propose that the photoionization of ground and excited neutral states, in a sequential two photon absorption mechanism, plays a role in the interpretation of the observed spectrum. The lowest vertical electron detachment energy of Na3O- corresponds to a Dyson orbital that is composed chiefly of diffuse Na s functions and connects a D3h singlet anion to an uncharged species with the same point group. Electron binding energies of isomers of the anion with different point groups or multiplicities have been considered. The relative magnitudes of the ionization energies of the neutral Li3O and Na3O species are also discussed. Whereas the most recent experimental data hold that Na3O has the higher ionization energy, this work asserts the opposite trend.

Zein, S.; Ortiz, J. V.

2012-06-01

132

Na+/K+-ATPase: Activity and inhibition  

NASA Astrophysics Data System (ADS)

The aim of the study was to give an overview of the mechanism of inhibition of Na+/K+-ATPase activity induced by some specific and non specific inhibitors. For this purpose, the effects of some ouabain like compounds (digoxin, gitoxin), noble metals complexes ([PtCl2DMSO2], [AuCl4]-, [PdCl4]2-, [PdCl(dien)]+, [PdCl(Me4dien)]+), transition metal ions (Cu2+, Zn2+, Fe2+, Co2+), and heavy metal ions (Hg2+, Pb2+, Cd2+) on the activity of Na+/K+-ATPase from rat synaptic plasma membranes (SPM), porcine cerebral cortex and human erythrocytes were discussed.

?olovi?, M.; Krsti?, D.; Krinulovi?, K.; Momi?, T.; Savi?, J.; Vuja?i?, A.; Vasi?, V.

2009-09-01

133

Involvement of na in active uptake of pyruvate in mesophyll chloroplasts of some c(4) plants : na/pyruvate cotransport.  

PubMed

An artificial Na(+) gradient across the envelope (Na(+) jump) enhanced pyruvate uptake in the dark into mesophyll chloroplasts of a C(4) plant, Panicum miliaceum (NAD-malic enzyme type) (J Ohnishi, R Kanai [1987] FEBS Lett 219:347). In the present study, (22)Na(+) and pyruvate uptake were examined in mesophyll chloroplasts of several species of C(4) plants. Enhancement of pyruvate uptake by a Na(+) jump in the dark was also seen in mesophyll chloroplasts of Urochloa panicoides and Panicum maximum (phosphoenolpyruvate carboxykinase types) but not in Zea mays or Sorghum bicolor (NADP-malic enzyme types). In mesophyll chloroplasts of P. miliaceum and P. maximum, pyruvate in turn enhanced Na(+) uptake in the dark when added together with Na(+). When flux of endogenous Na(+) was measured in these mesophyll chloroplasts preincubated with (22)Na(+), pyruvate addition induced Na(+) influx, and the extent of the pyruvate-induced Na(+) influx positively correlated with that of pyruvate uptake. A Na(+)/H(+) exchange ionophore, monensin, nullified all the above mutual effects of Na(+) and pyruvate in mesophyll chloroplasts of P. miliaceum, while it accelerated Na(+) uptake and increased equilibrium level of chloroplast (22)Na(+). Measurements of initial uptake rates of pyruvate and Na(+) gave a stoichiometry close to 1:1. These results point to Na(+)/pyruvate cotransport into mesophyll chloroplasts of some C(4) plants. PMID:16667876

Ohnishi, J; Flügge, U I; Heldt, H W; Kanai, R

1990-11-01

134

Manual de montaje del Telescopio Solar  

E-print Network

telescopio (LUNT 102 mm H) · Tapa del tubo · Tapa del prisma · Prisma · Buscador (instalado) · Ocular Zoom: (7.2 ­ 21.5 mm) · Tapas (x2) · Anillas para electrónica 8. Quitar tapas 9. Poner ocular 10.Alargar tubo 11.Colocar Parasol 12

135

Control del dolor: Apoyo para las personas con cáncer  

Cancer.gov

Libro sobre el control del dolor en pacientes con cáncer. Cubre los métodos y medicinas, así como los efectos físicos y emocionales del dolor. Es una adaptación cultural para el público de habla hispana del libro en inglés Pain Control.

136

Characterisation of sodium cations in dehydrated zeolite NaX by 23Na NMR spectroscopy.  

PubMed

23Na MAS, 2D nutation MAS, and DOR NMR spectroscopy has been applied to characterise the location of sodium cations in dehydrated zeolite NaX (Si/Al = 1.23). The 23Na MAS NMR spectra recorded at three different magnetic field strengths were decomposed by computer simulation into five lines, which were attributed to five crystallographically distinct cation sites known from X-ray diffraction studies. The assignments of the lines follow from electric field gradient calculations at the 23Na nuclei applying a simple point charge model based on crystal structure data. A weak Gaussian line at low field (delta iso = -6 ppm) is assigned to sodium cations at site I, two broad quadrupole patterns at the high-field side of the spectra are attributed to site I' (delta iso = -19 ppm, QCC = 5.2 MHz, eta = 0) and site II cations (delta iso = -15 ppm, QCC = 4.6 MHz, eta = 0), and two quadrupolar lines dominating the central region of the spectra originate from Na+ at two different III' sites (delta iso = -13 and -29 ppm, QCC = 2.6 and 1.6 MHz, eta = 0.7 and 0.9, respectively). Na+ ions located on a second I' site could be identified from the DOR NMR spectra. The line assignment is further corroborated by the reasonable agreement of the site occupancies estimated from the line intensities with those determined by X-ray diffraction. In addition, sodium site populations of five dehydrated zeolites NaX and NaY with Si/Al ratios between 1.09 and 4.0 were derived from the 23Na MAS NMR spectra. PMID:8986022

Feuerstein, M; Hunger, M; Engelhardt, G; Amoureux, J P

1996-11-01

137

Optics and Interferometry with Na2 Molecules  

Microsoft Academic Search

We have produced an intense, pure beam of sodium molecules (Na2) by using light forces to separate the atomic and molecular species in a seeded supersonic beam. We used diffraction from a microfabricated grating to study the atomic and molecular sodium in the beam. Using three of these gratings, we constructed a molecule interferometer with fully separated beams and high

Michael S. Chapman; Christopher R. Ekstrom; Troy D. Hammond; Richard A. Rubenstein; Jörg Schmiedmayer; Stefan Wehinger; David E. Pritchard

1995-01-01

138

Binding to Na+ exchanger regulatory factor 2  

E-print Network

Binding to Na+ /H+ exchanger regulatory factor 2 (NHERF2) affects trafficking and function in order to colonize and multiply in the human gut. Map, EspI and NleH1 are conserved EPEC effectors the trafficking of EspI to the Golgi and diminished the anti-apoptotic activity of NleH1. The binding of multiple

Hall, Randy A

139

master's degree NaNotechNology  

E-print Network

master's degree NaNotechNology When choosing a Master's programme, it is wise to look one step topical, incorporating the latest developments in applied physics, nanotechnology, chemical engineering projects will be carried out at the MESA+ institute for nanotechnology, or the MIRA institute

Twente, Universiteit

140

IV laser spectroscopy on NaI  

NASA Astrophysics Data System (ADS)

Using frequency-double laser radiation, fragmentary rotational fine structure was observed and assigned in the electronic transition 0 + - X 1? + of NaI for the first time. Adopting the semiclassical model of Child for predissociating states, molecular parameters were determined for the limiting diabatic and adiabatc states above the dissociation energy.

Schaefer, S. H.; Bender, D.; Tiemann, E.

1982-10-01

141

Single ionization of Na(3s) and Na*(3p) by low energy ion impact  

NASA Astrophysics Data System (ADS)

Single ionization cross sections for He2+ and O6+ impact on Na*(3p) in the 2-10 keV amu-1 energy range have been measured using recoil-ion momentum spectroscopy of cold Na atoms. The present results are compared with our previous data on Na(3s). It is found that ionization of these weakly bound alkali systems yields larger cross sections than predicted from scaling laws derived from H and He targets. Also information on the ejected electron momenta could be obtained from the recoil spectra.

Knoop, S.; Hasan, V. G.; Ott, H.; Morgenstern, R.; Hoekstra, R.

2006-04-01

142

Clausura de curso del Mster en Gestin Sostenible y Tecnologas del Agua de la Universidad de Alicante  

E-print Network

Clausura de curso del Máster en Gestión Sostenible y Tecnologías del Agua de la Universidad de el Tratamiento del Agua (ATTA) pronunciará la ponencia de clausura Finaliza el curso de los estudios oficiales del Máster en Gestión Sostenible y Tecnologías del Agua de la UA que imparte el Instituto del Agua

Escolano, Francisco

143

Luminescence of NaCl:Tl and NaCl:In at high pressure  

NASA Astrophysics Data System (ADS)

The effects of pressure up to 40 kbar and temperatures down to 100 °K on the intensity and lifetime of NaCa:Tl+ and NaCl:In has been studied. A kinetic model describing these luminescent properties has been proposed. The 3Tlu level is in thermal equilibrium with 3Alu. Both 3Tlu and 3Alu have nonradiative pathways to the ground state 1Alg. In addition 3Tlu is radiatively coupled to the ground state. Increasing pressure increases the radiative rate from 3Tlu to 1Alg and has no effect on the equilibrium between 3Tlu and 3Alu. The back feeding rate from 3Alu to 3Tlu is temperature sensitive for NaCl:Tl but not for NaCl:In.

Littman, J. E.; Drickamer, H. G.

1982-03-01

144

Kinetics of Na(+)-dependent conformational changes of rabbit kidney Na+,K(+)-ATPase.  

PubMed Central

The kinetics of Na(+)-dependent partial reactions of the Na+,K(+)-ATPase from rabbit kidney were investigated via the stopped-flow technique, using the fluorescent labels N-(4-sulfobutyl)-4-(4-(p-(dipentylamino)phenyl)butadienyl)py ridinium inner salt (RH421) and 5-iodoacetamidofluorescein (5-IAF). When covalently labeled 5-IAF enzyme is mixed with ATP, the two labels give almost identical kinetic responses. Under the chosen experimental conditions two exponential time functions are necessary to fit the data. The dominant fast phase, 1/tau 1 approximately 155 s-1 for 5-IAF-labeled enzyme and 1/tau 1 approximately 200 s-1 for native enzyme (saturating [ATP] and [Na+], pH 7.4 and 24 degrees C), is attributed to phosphorylation of the enzyme and a subsequent conformational change (E1ATP(Na+)3-->E2P(Na+)3 + ADP). The smaller amplitude slow phase, 1/tau 2 = 30-45 s-1, is attributed to the relaxation of the dephosphorylation/rephosphorylation equilibrium in the absence of K+ ions (E2P<==>E2). The Na+ concentration dependence of 1/tau 1 showed half-saturation at a Na+ concentration of 6-8 mM, with positive cooperatively involved in the occupation of the Na+ binding sites. The apparent dissociation constant of the high-affinity ATP-binding site determined from the ATP concentration dependence of 1/tau 1 was 8.0 (+/- 0.7) microM. It was found that P3-1-(2-nitrophenyl)ethyl ATP, tripropylammonium salt (NPE-caged ATP), at concentrations in the hundreds of micromolar range, significantly decreases the value of 1/tau 1, observed. This, as well as the biexponential nature of the kinetic traces, can account for previously reported discrepancies in the rates of the reactions investigated. PMID:9726935

Clarke, R J; Kane, D J; Apell, H J; Roudna, M; Bamberg, E

1998-01-01

145

¿Cómo puedo usar los servicios del CIS?  

Cancer.gov

El Servicio de Información sobre el Cáncer del Instituto Nacional del Cáncer maneja también la línea telefónica para dejar de fumar 1-877-448-7848 (1-877-44U-QUIT), la cual proporciona información gratuita para dejar de fumar y apoyo a fumadores que desean dejar el tabaco. Nuestro servicio no tiene ningún costo ni cuota de pago. El servicio se brinda en inglés y en español, de lunes a viernes de 8 de la mañana a 8 de la noche, hora del Este.

146

Na/beta-alumina/NaAlCl4, Cl2/C circulating cell  

NASA Technical Reports Server (NTRS)

A study was made of a high specific energy battery based on a sodium negative electrode and a chlorine positive electrode with molten AlCl3-NaCl electrolyte and a solid beta alumina separator. The basic performance of a Na beta-alumina NaAlCl4, Cl2/C circulating cell at 200 C was demonstrated. This cell can be started at 150 C. The use of melting sodium chloroaluminate electrolyte overcomes some of the material problems associated with the high working temperatures of present molten salt systems, such as Na/S and LiAl/FeS, and retains the advantages of high energy density and relatively efficient electrode processes. Preliminary investigations were conducted on a sodium-chlorine static cell, material compability, electrode design, wetting, and theoretical calculations to assure a better chance of success before assembling a Na/Cl2 circulating cell. Mathematical models provide a theoretical explanation for the performance of the NaCl2 battery. The results of mathematical models match the experimental results very well. According to the result of the mathematical modeling, an output at 180 mA/sq cm and 3.2 V can be obtained with optimized cell design.

Cherng, Jing-Yih; Bennion, Douglas N.

1987-01-01

147

Produccion Gaseosa del Cometa Halley: Erupciones Y Fotodisociacion del Radical OH  

NASA Astrophysics Data System (ADS)

RESUMEN:En este trabajo informamos la detecci6n de 20 erupciones en la li'nea de =18cm (1667MHz) del radical OH en el Cometa Halley.Las observaciones incluyen todos los monitoreos existentes y se extienden desde 120 dias antes del perihelio hasta 90 dias despues.Se detectan bruscos crecimientos en el flujo medido,hasta un factor 1O,seguidos por decaimientos lentos asociados con la fotodisociaci6n del OH. Se obtuvieron valores para el tiempo de vida fotoquimico del OH y del H2O basandose en el modelo desarrollado previamente por Silva(1988). Esos tiempos de vida estan de acuerdo con predicciones teoricas y con las observaciones en el Ultravioleta, y los resultados, los que son fuertemente dependientes de la velocidad heliocentrica del Coineta (variando hasta un factor 6), han sido calculados para varios rangos de velocidad entre +28 y -28 km/seg. Key wo'L :

Silva, A. M.; Mirabel, I. F.

1990-11-01

148

Amino group modification of (Na + +K + )ATPase  

Microsoft Academic Search

The effects of three amino group reagents on the activity of (Na++K+)-ATPase3 and its component K+-stimulatedp-nitrophenylphosphatase activity from rabbit kidney outer medulla have been studied. All three reagents cause inactivation of the enzyme. Modification of amino groups with trinitrobenzene sulfonic acid yields kinetics of inactivation of both activities, which depend on the type and concentration of the ligands present. In

J. J. H. H. M. De Pont; S. E. Emst-De Vries; S. L. Bonting

1984-01-01

149

LA GACETA 107 RESE ~NA DE LIBROS  

E-print Network

LA GACETA 107 RESE ~NA DE LIBROS DYNAMICAL SYSTEMS WITH APPLICATIONS USING MAPPLE Autor: Stephen libro publicado por alg´un autor ruso, no siempre f´acil de desci- frar. En los ´ultimos a~nos, sin los muchos libros que existen en el mercado y que van apareciendo cada d´ia. Una buena elecci´on ser

Rey Juan Carlos, Universidad

150

Inelastic and reactive collisions with polarized excited Na atoms  

SciTech Connect

Polarization effects in inelastic collisions of laser state-prepared Na(3/sup 2/P, M/sub J/) with Na/sup +/ leading to Na(3/sup 2/D) or Na(3/sup 2/S) are discussed for the energy range E/sub cm/ = 5-47.5eV. Studies with linearly polarized light can be explained with a simple ''locking'' model of the Na(P)-orbital. The investigations employing circularly polarized light are a very sensitive test of the models describing the nonadiabatic angular momentum coupling between electronic and nuclear motion. The dynamical effects of the electronic spin on the angular momentum transfer are discussed. Recent crossed-beam experiments on the Na + O/sub 2/ -> NaO = O reaction in the energy range E/sub cm/ = 0/3-0.8eV show a pronounced dependence on the electric electronic symmetry of Na. 17 refs., 11 figs.

Schmidt, H.; Hertel, I.V.; Lee, Y.T.

1985-07-01

151

An enhancement to the NA4 gear vibration diagnostic parameter  

NASA Technical Reports Server (NTRS)

A new vibration diagnostic parameter for health monitoring of gears, NA4*, is proposed and tested. A recently developed gear vibration diagnostic parameter NA4 outperformed other fault detection methods at indicating the start and initial progression of damage. However, in some cases, as the damage progressed, the sensitivity of the NA4 and FM4 parameters tended to decrease and no longer indicated damage. A new parameter, NA4* was developed by enhancing NA4 to improve the trending of the parameter. This allows for the indication of damage both at initiation and also as the damage progresses. The NA4* parameter was verified and compared to the NA4 and FM4 parameters using experimental data from single mesh spur and spiral bevel gear fatigue rigs. The primary failure mode for the test cases was naturally occurring tooth surface pitting. The NA4* parameter is shown to be a more robust indicator of damage.

Decker, Harry J.; Handschuh, Robert F.; Zakrajsek, James J.

1994-01-01

152

An enhancement to the NA4 gear vibration diagnostic parameter  

NASA Astrophysics Data System (ADS)

A new vibration diagnostic parameter for health monitoring of gears, NA4*, is proposed and tested. A recently developed gear vibration diagnostic parameter NA4 outperformed other fault detection methods at indicating the start and initial progression of damage. However, in some cases, as the damage progressed, the sensitivity of the NA4 and FM4 parameters tended to decrease and no longer indicated damage. A new parameter, NA4* was developed by enhancing NA4 to improve the trending of the parameter. This allows for the indication of damage both at initiation and also as the damage progresses. The NA4* parameter was verified and compared to the NA4 and FM4 parameters using experimental data from single mesh spur and spiral bevel gear fatigue rigs. The primary failure mode for the test cases was naturally occurring tooth surface pitting. The NA4* parameter is shown to be a more robust indicator of damage.

Decker, Harry J.; Handschuh, Robert F.; Zakrajsek, James J.

1994-07-01

153

Progress of the NA62 RICH detector  

NASA Astrophysics Data System (ADS)

NA62 is the last generation Kaon experiment at CERN. Its main goal is to collect about 100 K+??+?bar nu events with 10% background. This implies to collect more than 1013 K+ decays with a backgound rejection factor better than 1012. The challenging aspect of the experiment is the suppression of Kaon decays with branching ratioes up to 10 orders of magnitude higher than the signal and similar experimental signature, such as K+??+?. To this purpose good PID (Particle IDentification) and kinematic rejection are required. Precise timing is also needed to correctly associate the ?+ with the parent K+ in an high rate environment. A RICH (Ring Imaging Cherenkov) detector is proposed as PID element, to identify ? contaminating the ? sample in the 15-35 GeV/c momentum range with inefficiency lower than 1% and to measure the arrival time with precision smaller than 100 ps. It will also be a key element for the NA62 trigger. A vacuum-proof cylindrical vessel with 4 m diameter, 17 m long, will be filled with Neon gas at atmospheric pressure. The Cherenkov light will be reflected by a mosaic of 20 hexagonal mirrors with 17 m focal length and collected by 2000 photomultipliers. The progress in the construction of the detector is described: the installation will start in January 2014, with completion foreseen in time for the first physics run of the NA62 experiment in the fall of 2014.

Lenti, Massimo

2014-01-01

154

Resonances production from the NA60 experiment  

NASA Astrophysics Data System (ADS)

The NA60 experiment at the CERN SPS has studied light vector meson production in In-In collisions at 158A GeV. The ? meson was detected via both the K+K- and the ?+?- decay channels. The yields and inverse slope parameters of the mT spectra observed in the two channels are compatible within errors, different from the large discrepancies seen in Pb-Pb collisions between the hadronic (NA49) and dimuon (NA50) decay channels. In the invariant mass region 0.2 < M?? < 2.6 GeV, a strong excess of pairs above the sources that describe the mass spectrum in p-A collisions is observed. The mass spectrum for M?? < 1 GeV is consistent with a dominant contribution from the pion annihilation process ? + ? ? ? ? ?+?-. For M?? > 1 GeV, the excess is found to be prompt, with remarkable differences with respect to the Drell-Yan process. The Teff slope parameter, extracted from the transverse mass spectra, shows a rise with mass up to the ?, followed by a sudden decline for higher masses. The former is consistent with radial flow of a hadronic source, while the latter suggests a dominantly partonic emission source.

De Falco, A.

2012-11-01

155

Determining Neutron Multiplicity in MoNA  

NASA Astrophysics Data System (ADS)

The Modular Neutron Array, located at the NSCL at Michigan State University, is used in conjunction with the MSU/FSU Sweeper Magnet to study the breakup of neutron-rich nuclei. Fragmentation reactions create particle-unstable nuclei near the neutron dripline which spontaneously breakup by the decay of one or two neutrons with energies that reflect the nuclear structure of unbound excited and ground states. The neutrons continue forward into MoNA where their position and time are recorded, and the charged fragments' position and energy are measured by the array of detectors following the Sweeper Magnet. The neutron decay energies can then be determined using kinematic reconstruction of the breakup. It is important to distinguish between one- and two-neutron decays in MoNA. We have therefore developed an algorithm that helps determine neutron multiplicity, based on energy and momentum conservation restrictions for single neutrons scattering multiple times in MoNA. Results of this approach to the analysis of ^12Be and ^11Be decay will be presented.

Gillette, J.; Gardner, M.; Reed, A.; Rogers, W. F.; Mosby, S.

2007-10-01

156

28 de mayo del 2007 Curriculum Vitae  

E-print Network

de la Organizaciâ??on de Estados Americanos. 1987 Premio Dudley del Observatorio Dudley. 1988 Becaâ??es Organizadores de las Siguientes Reuniones (29): Symposium on Herbig­Haro Objects, T Tauri Stars and Related

Rodriguez, Luis F.

157

28 de mayo del 2007 Curriculum Vitae  

E-print Network

de la Organizaci´on de Estados Americanos. 1987 Premio Dudley del Observatorio Dudley. 1988 Beca´es Organizadores de las Siguientes Reuniones (29): Symposium on Herbig-Haro Objects, T Tauri Stars and Related

Rodriguez, Luis F.

158

A 23Na magic angle spinning nuclear magnetic resonance, XANES, and high-temperature X-ray diffraction study of NaUO3, Na4UO5, and Na2U2O7.  

PubMed

The valence state of uranium has been confirmed for the three sodium uranates NaU(V)O3/[Rn](5f(1)), Na4U(VI)O5/[Rn](5f(0)), and Na2U(VI)2O7/[Rn](5f(0)), using X-ray absorption near-edge structure (XANES) spectroscopy. Solid-state (23)Na magic angle spinning nuclear magnetic resonance (MAS NMR) measurements have been performed for the first time, yielding chemical shifts at -29.1 (NaUO3), 15.1 (Na4UO5), and -14.1 and -19 ppm (Na1 8-fold coordinated and Na2 7-fold coordinated in Na2U2O7), respectively. The [Rn]5f(1) electronic structure of uranium in NaUO3 causes a paramagnetic shift in comparison to Na4UO5 and Na2U2O7, where the electronic structure is [Rn]5f(0). A (23)Na multi quantum magic angle spinning (MQMAS) study on Na2U2O7 has confirmed a monoclinic rather than rhombohedral structure with evidence for two distinct Na sites. DFT calculations of the NMR parameters on the nonmagnetic compounds Na4UO5 and Na2U2O7 have permitted the differentiation between the two Na sites of the Na2U2O7 structure. The linear thermal expansion coefficients of all three compounds have been determined using high-temperature X-ray diffraction: ?a = 22.7 × 10(-6) K(-1), ?b = 12.9 × 10(-6) K(-1), ?c = 16.2 × 10(-6) K(-1), and ?vol = 52.8 × 10(-6) K(-1) for NaUO3 in the range 298-1273 K; ?a = 37.1 × 10(-6) K(-1), ?c = 6.2 × 10(-6) K(-1), and ?vol = 81.8 × 10(-6) K(-1) for Na4UO5 in the range 298-1073 K; ?a = 6.7 × 10(-6) K(-1), ?b = 14.4 × 10(-6) K(-1), ?c = 26.8 × 10(-6) K(-1), ?? = -7.8 × 10(-6) K(-1), and ?vol = -217.6 × 10(-6) K(-1) for Na2U2O7 in the range 298-573 K. The ? to ? phase transition reported for the last compound above about 600 K was not observed in the present studies, either by high-temperature X-ray diffraction or by differential scanning calorimetry. PMID:24350659

Smith, A L; Raison, P E; Martel, L; Charpentier, T; Farnan, I; Prieur, D; Hennig, C; Scheinost, A C; Konings, R J M; Cheetham, A K

2014-01-01

159

Na+/H+ and Na+/NH+4 activities of zebrafish NHE3b expressed in Xenopus oocytes.  

PubMed

Zebrafish Na(+)/H(+) exchanger 3b (zNHE3b) is highly expressed in the apical membrane of ionocytes where Na(+) is absorbed from ion-poor fresh water against a concentration gradient. Much in vivo data indicated that zNHE3b is involved in Na(+) absorption but not leakage. However, zNHE3b-mediated Na(+) absorption has not been thermodynamically explained, and zNHE3b activity has not been measured. To address this issue, we overexpressed zNHE3b in Xenopus oocytes and characterized its activity by electrophysiology. Exposure of zNHE3b oocytes to Na(+)-free media resulted in significant decrease in intracellular pH (pH(i)) and intracellular Na(+) activity (aNa(i)). aNa(i) increased significantly when the cytoplasm was acidified by media containing CO?-HCO?(-) or butyrate. Activity of zNHE3b was inhibited by amiloride or 5-ethylisopropyl amiloride (EIPA). Although the activity was accompanied by a large hyperpolarization of ?50 mV, voltage-clamp experiments showed that Na(+)/H(+) exchange activity of zNHE3b is electroneutral. Exposure of zNHE3b oocytes to medium containing NH?/NH?(+) resulted in significant decreases in pH(i) and aNa(i) and significant increase in intracellular NH?(+) activity, indicating that zNHE3b mediates the Na(+)/NH?(+) exchange. In low-Na(+) (0.5 mM) media, zNHE3b oocytes maintained aNa(i) of 1.3 mM, and Na(+)-influx was observed when pHi was decreased by media containing CO?-HCO?(-) or butyrate. These results provide thermodynamic evidence that zNHE3b mediates Na(+) absorption from ion-poor fresh water by its Na(+)/H(+) and Na(+)/NH?(+) exchange activities. PMID:24401990

Ito, Yusuke; Kato, Akira; Hirata, Taku; Hirose, Shigehisa; Romero, Michael F

2014-03-01

160

Angiotensin II-induced hypertension increases plasma membrane Na pump activity by enhancing Na entry in rat thick ascending limbs.  

PubMed

Thick ascending limbs (TAL) reabsorb 30% of the filtered NaCl load. Na enters the cells via apical Na-K-2Cl cotransporters and Na/H exchangers and exits via basolateral Na pumps. Chronic angiotensin II (ANG II) infusion increases net TAL Na transport and Na apical entry; however, little is known about its effects on the basolateral Na pump. We hypothesized that in rat TALs Na pump activity is enhanced by ANG II-infusion, a model of ANG II-induced hypertension. Rats were infused with 200 ng·kg(-1)·min(-1) ANG II or vehicle for 7 days, and TAL suspensions were obtained. We studied plasma membrane Na pump activity by measuring changes in 1) intracellular Na (Nai) induced by ouabain; and 2) ouabain-sensitive oxygen consumption (QO2). We found that the ouabain-sensitive rise in Nai in TALs from ANG II-infused rats was 12.8 ± 0.4 arbitrary fluorescent units (AFU)·mg(-1)·min(-1) compared with only 9.9 ± 1.1 AFU·mg(-1)·min(-1) in controls (P < 0.024). Ouabain-sensitive oxygen consumption was 17 ± 5% (P < 0.043) greater in tubules from ANG II-treated than vehicle rats. ANG II infusion did not alter total Na pump expression, the number of Na pumps in the plasma membrane, or the affinity for Na. When furosemide (1.1 mg·kg(-1)·day(-1)) was coinfused with ANG II, no increase in plasma membrane Na pump activity was observed. We concluded that in ANG II-induced hypertension Na pump activity is increased in the plasma membrane of TALs and that this increase is caused by the chronically enhanced Na entry occurring in this model. PMID:23986517

Gonzalez-Vicente, Agustin; Garvin, Jeffrey L

2013-11-01

161

23Na multiple quantum filtered NMR characterisation of Na+ binding and dynamics in animal cells: a comparative study and effect of Na+/Li + competition.  

PubMed

Double quantum and triple quantum filtered (23)Na nuclear magnetic resonance techniques were used to characterise in detail the isotropic and anisotropic binding and dynamics of intra- and extracellular Na(+) in different cellular systems, in the absence and presence of Li(+). The kinetics of Li(+) influx by different cell types was evaluated. At steady state, astrocytes accumulated more Li(+) than red blood cells (RBCs), while a higher intracellular Li(+) concentration was found in chromaffin than in SH-SY5Y cells. Anisotropic and isotropic motions were detected for extracellular Na(+) in all cellular systems studied. Isotropic intracellular Na(+) motions were observed in all types of cells, while anisotropic Na(+) motions in the intracellular compartment were only detected in RBCs. (23)Na triple quantum signal efficiency for intracellular Na(+) was SH-SY5Y > chromaffin > RBCs, while the reverse order was observed for the extracellular ions. (23)Na double quantum signal efficiency for intracellular Na(+) was non-zero only in RBCs, and for extracellular Na(+) the order RBCs > chromaffin > SH-SY5Y cells was observed. Li(+) loading generally decreased intracellular Na(+) isotropic movements in the cells, except for astrocytes incubated with a low Li(+) concentration and increased anisotropic intracellular Na(+) movements in RBCs. Li(+) effects on the extracellular signals were more complex, reflecting Li(+)/Na(+) competition for isotropic and anisotropic binding sites at the extracellular surface of cell membranes and also at the surface of the gel used for cell immobilisation. These results are relevant and contribute to the interpretation of the in vivo pharmacokinetics and sites of Li(+) action. PMID:23563802

Fonseca, Carla P; Fonseca, Luís L; Montezinho, Liliana P; Alves, Paula M; Santos, Helena; Castro, M Margarida C A; Geraldes, Carlos F G C

2013-07-01

162

Modelo Hidrulico Operacional del Oeste de Puerto Rico  

E-print Network

Puerto Rico Introducción El Instituto de Investigaciones Sobre Recursos de Agua y el Ambiente de Puerto del Modelo Hidráulico Operacional del Sistema de Distribución de Agua del Oeste de Puerto Rico. El agua. · Reserva Nodos que representan una fuente de agua externa del sistema. · Tanques Nodos con

Gilbes, Fernando

163

Departamento de Filosofa del Derecho y Derecho Internacional Privado Presentacin  

E-print Network

Departamento de Filosofía del Derecho y Derecho Internacional Privado Presentación El Departamento de Filosofía del Derecho y Derecho Internacional Privado está compuesto por las siguientes áreas de personalizada, los profesores del Departamento de Filosofía del Derecho y Derecho Internacional Privado ruegan

Escolano, Francisco

164

MONITOR DE CICLO INDOOR OBJETIVOS DEL CURSO  

E-print Network

positivos y posibles perjuicios que puede tener la práctica del ciclo indoor e indoor walking sobre la salud Julián Álvarez García, Médico, Especialista en Medicina de la EF y el Deporte, Doctor en Medicina, Experto en Fisiología del Ejercicio, Profesor de Medicina Deportiva de la UMH, Asesor médico de la

Escolano, Francisco

165

Cronología acotada de la década del '80  

E-print Network

Alezzo. Teatro Regina. (Abril) Marathón, de Ricardo Monti. Dirección: Jaime Kogan. Teatro: Los teatros de San Telmo. La puesta estuvo a cargo del Equipo del Teatro Payró. La ubicamos como textualidad emergente de los '70. Es una alegoría con... discurso marginal de la radio y la historieta. Con este intertexto más el material que le proporcionan las películas de una época, recrea un mundo de nostalgia: el paso de la niñez a la adolescencia. (Agosto) Extraño juguete, de Susan Torres Molina...

Cazap, S.; Giustachini, A.; Massa, C.; Semelman, A.; Sikora, Marina F.

1991-04-01

166

La evolucion del modernismo en Puerto Rico  

E-print Network

metros e hizo uso del encabal- gamiento y de la cesura en mitad de sus versos, cambiando asi el antiguo romance (Franco 151). Ademas, Dario resucito la cuaderna via medieval y el verso alejandrino. Ruben Dario descubrio nuevas posibilidades foneticas... metros e hizo uso del encabal- gamiento y de la cesura en mitad de sus versos, cambiando asi el antiguo romance (Franco 151). Ademas, Dario resucito la cuaderna via medieval y el verso alejandrino. Ruben Dario descubrio nuevas posibilidades foneticas...

Gonzalez-Hernandez, Miriam Mercedes

2012-06-07

167

MANUAL TELESCOPIO MONS OBSERVATORIO DEL TEIDE  

E-print Network

electr´onica Se trata de una funci´on del operardor nocturno (Ap´endice C). 1.2. Tapas de la ´optica Para proteger la ´optica del telescopio hay dos tapas, una para el telescopio principal y otra para el buscador. La maniobra para quitarlas o colocarlas tiene cierto peligro, debido a que el peso de ambas tapas

168

Orígenes y desarrollo del teatro guatemalteco.  

E-print Network

teatral bifurcado en dos corrientes muy definidas—la de nuestro mundo indígena y la de nuestro mundo mestizo. La primera se desborda por los pueblos del interior del país, a la sombra de las iglesias, en los patios de las alcaldías municipales o en las... sutil, más amable por menos sangriento, pero muy eficaz para lograr la total cristianización de aquellos pueblos, apareció el teatro inmediatamente después de la conquista. Se adaptaron las danzas locales, 42 LATIN AMERICAN THEATRE REVIEW...

Carrillo, Hugo

1971-10-01

169

Calidad de Imagen del Telescopio UNAM212  

NASA Astrophysics Data System (ADS)

El telescopio UNAM2l2, del Observatorio Astronómico Nacional, situado en la Sierra de San Pedro Mártir (Baja California, México), cumplira en un futuro muy cercano siete años de uso para fines de investigación astronómica. Aunque en este tiempo no se ha efectuado un estudio sistemático acerca de su comportamiento óptico y de los factores que influyen en la calidad de las imágenes, se han realizado pruebas diversas, estudios parciales y reuniones especificas, cuyos resultados no siempre se han difundido ampliamente y generalmente no se han presentado por escrito. Es por ello que hemos creido necesario intentar una recopilación de la información existente para poder con ella establecer un diagnóstjco que, aunque no sea definitivo, sirva de base para futuros trabajos tendientes a optimizar el comportamiento óptico del telescopio. Es evidente que un buen número de las conclusiones que se presentan son resultado del trabajo de muchas personas ó de esfuerzos colectivos. Asimismo, hemos tratado de localizar información bibliográfica que pueda ser de utilidad. Nuestro objetivo primordial ha consistido en centrarnos en la óptica del telescopio y su calidad, pero también se han considerado otros aspectos que puedan afectar las imágenes obtenidas tales como: celda del primario, `seeing' local y externo, flexiones posibles en la estructura mecánica del telescopio, etc.

Cobos, F. J.; Teiada de Vargas, C.

1987-05-01

170

Advanced Intermediate-Temperature Na-S Battery  

SciTech Connect

In this study, we reported an intermediate-temperature (~150°C) sodium-sulfur (Na-S) battery. With a reduced operating temperature, this novel battery can potentially reduce the cost and safety issues associated with the conventional high-temperature (300~350°C) Na-S battery. A dense ?"-Al2O3 solid membrane and tetraglyme were utilized as the electrolyte separator and catholyte solvent in this battery. Solubility tests indicated that cathode mixture of Na2S4 and S exhibited extremely high solubility in tetraglyme (e.g., > 4.1 M for Na2S4 + 4 S). CV scans of Na2S4 in tetraglyme revealed two pairs of redox couples with peaks at around 2.22 and 1.75 V, corresponding to the redox reactions of polysulfide species. The discharge/charge profiles of the Na-S battery showed a slope region and a plateau, indicating multiple steps and cell reactions. In-situ Raman measurements during battery operation suggested that polysulfide species were formed in the sequence of Na2S5 + S ? Na2S5 + Na2S4? Na2S4 + Na2S2 during discharge and in a reverse order during charge. This battery showed dramatic improvement in rate capacity and cycling stability over room-temperature Na-S batteries, which makes it attractive for renewable energy integration and other grid related applications.

Lu, Xiaochuan; Kirby, Brent W.; Xu, Wu; Li, Guosheng; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.; Yang, Zhenguo (Gary) [Gary

2013-01-01

171

Influence of Salt Purity on Na+ and Palmitic Acid Interactions  

E-print Network

Influence of Salt Purity on Na+ and Palmitic Acid Interactions Zishuai Huang, Wei Hua, Dominique of salt purity on the interactions between Na+ ions and the carboxylate (COO- ) head group of palmitic frequency generation (VSFG) spectroscopy. Ultrapure (UP) and ACS grade NaCl salts are used for aqueous

172

Rigidification of the autolysis loop enhances Na+ binding to thrombin  

E-print Network

Rigidification of the autolysis loop enhances Na+ binding to thrombin Nicola Pozzi, Raymond Chen April 2011 Keywords: Thrombin Na+ binding Allostery X-ray crystallography Binding of Na+ to thrombin+ with thrombin and possibly increase catalytic activity under physiological conditions have so far been

Di Cera, Enrico

173

Electrochemical Properties of Monoclinic NaNiO2  

E-print Network

Monoclinic NaNiO[subscript 2] is re-investigated as a positive electrode material for sodium ion batteries. We observe reversible Na extraction and insertion of about 120 mAh/g when NaNiO[subscript 2] is cycled between ...

Vassilaras, Plousia E.

174

Precio del agua y relocalización del recurso en la economía andaluza. Una aproximación desde un modelo de equilibrio general aplicado  

Microsoft Academic Search

El objetivo de este trabajo consiste en analizar los efectos que tendría un incremento en la tarifa del agua del sector agrario sobre la conservación del recurso, la eficiencia en el consumo y la posible relocalización del mismo entre los diferentes sectores productivos. La política tarifaria se aplicará sobre el sector agrario debido, por un lado, al excesivo consumo de

M. Alejandro Cardenete; G. J. D. Hewings; E. Velázquez

2005-01-01

175

Zero-gravity growth of NaF-NaCl eutectics in the NASA Skylab program  

NASA Technical Reports Server (NTRS)

Continuous and discontinuous NaF fibers, embedded in a NaCl matrix, were produced in space and on earth. The production of continuous fibers in a eutectic mixture is attributed to the absence of convection current in the liquid during solidification in space. Image transmission and optical transmittance measurements of transverse sections of the space-grown and earth-grown ingots were made with a light microscope and a spectrometer. It is shown that better optical properties were obtained from samples grown in space. This was attributed to a better alignment of NaF fibers along the ingot axis. A new concept is advanced to explain the phenomenon of transmittance versus far infrared wavelength of the directionally solidified NaCl-NaF eutectic in terms of the two-dimensional Bragg Scattering and the polarization effect of Rayleigh scattering. This concept can be applied to other eutectic systems as long as the index of refraction of the matrix over a range of wavelengths is known. Experimental data are in agreement with the theoretical prediction.

Yue, A. S.; Allen, F. G.; Yu, J. G.

1976-01-01

176

Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps  

PubMed Central

A single Na+/K+-ATPase pumps three Na+ outwards and two K+ inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na+ than K+ generates outward current across the cell membrane. Less well understood is the ability of Na+/K+ pumps to generate an inward current of protons. Originally noted in pumps deprived of external K+ and Na+ ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K+ and Na+ concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na+ release from phosphorylated Na+/K+ pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na+/K+ pumps that enables proton import is not required for completion of the 3 Na+/2 K+ transport cycle. However, the back-step occurs readily during Na+/K+ transport when external K+ ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na+-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na+ and K+ ions that passes through binding site II. The inferred occurrence of Na+/K+ exchange and H+ import during the same conformational cycle of a single molecule identifies the Na+/K+ pump as a hybrid transporter. Whether Na+/K+ pump–mediated proton inflow may have any physiological or pathophysiological significance remains to be clarified. PMID:24688018

Vedovato, Natascia

2014-01-01

177

Na double-edge magneto-optic filter for Na lidar profiling of wind and temperature in the  

E-print Network

Na double-edge magneto-optic filter for Na lidar profiling of wind and temperature in the lower Doppler lidars measure wind and temperature simultaneously in the meso- sphere and lower thermosphere [1-edge magneto-optic filter is proposed for incorporation into the receiver of a three-frequency Na Doppler lidar

Chu, Xinzhao

178

Molecular mechanism of Na(+),K(+)-ATPase malfunction in mutations characteristic of adrenal hypertension.  

PubMed

Mutations within ion-transporting proteins may severely affect their ability to traffic ions properly and thus perturb the delicate balance of ion gradients. Somatic gain-of-function mutations of the Na(+),K(+)-ATPase ?1-subunit have been found in aldosterone-producing adenomas that are among the causes of hypertension. We used molecular dynamics simulations to investigate the structural consequences of these mutations, namely, Leu97 substitution by Arg (L97R), Val325 substitution by Gly (V325G), deletion of residues 93-97 (Del93-97), and deletion-substitution of residues 953-956 by Ser (EETA956S), which shows inward leak currents under physiological conditions. The first three mutations affect the structural context of the key ion-binding residue Glu327 at binding site II, which leads to the loss of the ability to bind ions correctly and to occlude the pump. The mutated residue in L97R is more hydrated, which ultimately leads to the observed proton leak. V325G mimics the structural behavior of L97R; however, it does not promote the hydration of surrounding residues. In Del93-97, a broader opening is observed because of the rearrangement of the kinked transmembrane helix 1, M1, which may explain the sodium leak measured with the mutant. The last mutant, EETA956S, opens an additional water pathway near the C-terminus, affecting the III sodium-specific binding site. The results are in excellent agreement with recent electrophysiology measurements and suggest how three mutations prevent the occlusion of the Na(+),K(+)-ATPase, with the possibility of transforming the pump into a passive ion channel, whereas the fourth mutation provides insight into the sodium binding in the E1 state. PMID:24428543

Kopec, Wojciech; Loubet, Bastien; Poulsen, Hanne; Khandelia, Himanshu

2014-02-01

179

Determination of Na(2)O from sodium aluminate NaAlO(2).  

PubMed

The aim of the work was to find a suitable method and conditions for determining Na(2)O wt.% from NaAlO(2). Problems were encountered while titrating NaAlO(2) with hydrochloric acid. The problematic area was the pH range 4-10 where aluminum precipitates as hydroxides. The different species of the aluminate solution were determined using potentiometric and complexometric titrations. The equivalent point of the potentiometric titration was detected using Gran's plotting method. Precipitation of aluminum hydroxides did not interfere with titrations, because in potentiometric titrations the pH value was over 10 and in complexometric titrations the pH was 4. The results were accurate and determinations were easy to carry out. Sodium was also determined by DCP-AES. PMID:18968035

Näykki, T; Raimo, A; Paavo, P; Antero, K; Päivi, N

2000-07-31

180

Shank2 redistributes with NaPilla during regulated endocytosis  

PubMed Central

Serum phosphate levels are acutely impacted by the abundance of sodium-phosphate cotransporter IIa (NaPiIIa) in the apical membrane of renal proximal tubule cells. PSD-95/Disks Large/Zonula Occludens (PDZ) domain-containing proteins bind NaPiIIa and likely contribute to the delivery, retention, recovery, and trafficking of NaPiIIa. Shank2 is a distinctive PDZ domain protein that binds NaPiIIa. Its role in regulating NaPiIIa activity, distribution, and abundance is unknown. In the present in vivo study, rats were maintained on a low-phosphate diet, and then plasma phosphate levels were acutely elevated by high-phosphate feeding to induce the recovery, endocytosis, and degradation of NaPiIIa. Western blot analysis of renal cortical tissue from rats given high-phosphate feed showed NaPiIIa and Shank2 underwent degradation. Quantitative immunofluorescence analyses, including microvillar versus intracellular intensity ratios and intensity correlation quotients, showed that Shank2 redistributed with NaPiIIa during the time course of NaPiIIa endocytosis. Furthermore, NaPiIIa and Shank2 trafficked through distinct endosomal compartments (clathrin, early endosomes, lysosomes) with the same temporal pattern. These in vivo findings indicate that Shank2 is positioned to coordinate the regulated endocytic retrieval and downregulation of NaPiIIa in rat renal proximal tubule cells. PMID:20810910

Dobrinskikh, Evgenia; Giral, Hector; Caldas, Yupanqui A.; Levi, Moshe

2010-01-01

181

Dr. Matas Alvarado (CV breve) Investigador Titular del Departamento de Computacin del CINVESTAV; Miembro Regular de  

E-print Network

Dr. Matías Alvarado (CV breve) Investigador Titular del Departamento de Computación del CINVESTAV. JOS� MATÍAS ALVARADO MENTADO Curriculum Vitae DATOS PROFESIONALES Investigador CINVESTAV 3B (Febrero JCR ISI 1. Alvarado Matias, Sheremetov, L., Bañares, R. & Cantú, F. (Guest Eds.) Special Issue

Alvarado, Matías

182

Preguntas y respuestas acerca del Estudio del Tamoxifeno y Raloxifeno (STAR)  

Cancer.gov

El Estudio del Tamoxifeno y Raloxifeno (STAR, por sus siglas en inglés) es un estudio clínico (un estudio de investigación conducido con voluntarios) diseñado para ver cómo el medicamento raloxifeno (Evista®) se compara con el medicamento tamoxifeno (Nolvadex®) en reducir la incidencia de cáncer del seno en las mujeres con alto riesgo de desarrollar la enfermedad.

183

DECISIONES DE FINANCIACIÓN DE LA INDUSTRIA METALMECÁNICA DEL VALLE DEL CAUCA  

Microsoft Academic Search

Esta investigación tiene como objetivo conocer los factores que influyen en la toma de decisiones de financiamiento a largo plazo en la industria metalmecánica del Valle del Cauca (Colombia), hasta ahora no explorados. Se realiza un estudio para el periodo 2000-2006, utilizando como método, el análisis de la estructura financiera y la aplicación de un modelo econométrico de Datos de

JORGE ALBERTO RIVERA GODOY

2008-01-01

184

Localización del Esfuerzo de Pesca en la Pesquería Chileno-Transzonal del Jurel (Trachurus murphyi)  

Microsoft Academic Search

Este trabajo analiza condicionantes de la localización del esfuerzo pesquero de la flota chilena que opera en la pesquería transzonal del Jurel, considerando datos por viaje para el periodo 1987-2004. Desde principios de los años 1990s esta flota comenzó a desplazarse más allá de las 200 mn, condicionada por cambios en la distribución espacial de este recurso. Se presume que

Julio Peña Torres; Mabyr Valderrama

2008-01-01

185

Boletín del Instituto Nacional del Cáncer - 3 de enero de 2012  

Cancer.gov

Dra. Rachel Ballard-Barbash Nuevos indicios del papel de la obesidad en el cáncer A medida que ha aumentado la prevalencia de la obesidad alrededor del mundo, se ha incrementado también la preocupación sobre sus consecuencias en la salud pública. Los índices de obesidad se han más que duplicado desde 1980, según la Organización Mundial de la Salud.

186

Standardization method of ²²Na using two NaI(Tl) scintillation detectors.  

PubMed

A new standardization method for a sealed (22)Na point source was developed utilizing two NaI(Tl) scintillation detectors. In the proposed method, the count rates of annihilation radiation, gamma rays, their coincidence sum, and the coincidences between the two detectors are used. The equations from which the source activity can be deduced are derived in this work. A series of EGS-5 Monte Carlo calculations were conducted to test the validity of the expressions. The calculated activity agreed within approximately 1 percent with the literature data used as input in the simulations. PMID:24411317

Sato, Y; Yamada, T; Hasegawa, T

2014-05-01

187

O Teatro Brasileiro na Década de Oitenta  

E-print Network

Buenos Aires. O crepúsculo da década de setenta e o raiar dos anos oitenta também testemunharam as primeiras edições e/ou encenações de vários tratamentos dramáticos de um dos pilares da ditadura-a tortura. Milagre na cela, de Jorge Andrade, estreou... década de oitenta explica-se, ao menos em parte, pelas experiências dos que foram mais de perto atingidos pela censura da ditadura. Com a liberalização política, Boal voltou ao Brasil pela primeira vez em oito anos para dar palestras e dirigir...

Albuquerque, Severino Joã o

1992-04-01

188

High [Na+]i in cardiomyocytes from rainbow trout.  

PubMed

Intracellular Na(+)-concentration, [Na(+)](i) modulates excitation-contraction coupling of cardiac myocytes via the Na(+)/Ca(2+) exchanger (NCX). In cardiomyocytes from rainbow trout (Oncorhyncus mykiss), whole cell patch-clamp studies have shown that Ca(2+) influx via reverse-mode NCX contributes significantly to contraction when [Na(+)](i) is 16 mM but not 10 mM. However, physiological [Na(+)](i) has never been measured. We recorded [Na(+)](i) using the fluorescent indicator sodium-binding benzofuran isophthalate in freshly isolated atrial and ventricular myocytes from rainbow trout. We examined [Na(+)](i) at rest and during increases in contraction frequency across three temperatures that span those trout experience in nature (7, 14, and 21 degrees C). Surprisingly, we found that [Na(+)](i) was not different between atrial and ventricular cells. Furthermore, acute temperature changes did not affect [Na(+)](i) in resting cells. Thus, we report a resting in vivo [Na(+)](i) of 13.4 mM for rainbow trout cardiomyocytes. [Na(+)](i) increased from rest with increases in contraction frequency by 3.2, 4.7, and 6.5% at 0.2, 0.5, and 0.8 Hz, respectively. This corresponds to an increase of 0.4, 0.6, and 0.9 mM at 0.2, 0.5, and 0.8 Hz, respectively. Acute temperature change did not significantly affect the contraction-induced increase in [Na(+)](i). Our results provide the first measurement of [Na(+)](i) in rainbow trout cardiomyocytes. This surprisingly high [Na(+)](i) is likely to result in physiologically significant Ca(2+) influx via reverse-mode NCX during excitation-contraction coupling. We calculate that this Ca(2+)-source will decrease with the action potential duration as temperature and contraction frequency increases. PMID:17507438

Birkedal, Rikke; Shiels, Holly A

2007-08-01

189

Use of ²³Na-nuclear magnetic resonance to follow sodium uptake and efflux in NaCl-adapted and nonadapted millet (Panicum miliaceum) suspensions  

Microsoft Academic Search

Cellular Na\\/sup +\\/ transport was followed in vivo by ²³Na nuclear magnetic resonance (NMR) using anionic dysprosium-based shift reagents to resolve internal and external ²³Na\\/sup +\\/ resonances. Proso millet (Panicum miliaceum) cell suspensions adapted for rapid growth on 130 mM NaCl had biphasic ²³Na efflux kinetics when shifted to low Na..mu.. medium, while nonadapted cells had little measurable Na\\/sup +\\/

L. O. Sillerud; J. W. Heyser

1984-01-01

190

Impacto economico del turismo en el Mercosur y Chile (1990-2000)  

Microsoft Academic Search

El objetivo del presente trabajo consiste en describir la situacion del turismo actual y analizar la evolucion del turismo receptivo en la region del MERCOSUR y Chile en la decada de los noventa. Tambien se propone un modelo econometrico que recoge el impacto positivo del turismo en el crecimiento del PIB del sector servicios. This paper describes present situation of

Rodrigo Gardella; Eva Aguayo

2002-01-01

191

Na? transport in the normal and failing heart - remember the balance.  

PubMed

In the heart, intracellular Na(+) concentration ([Na(+)]i) is a key modulator of Ca(2+) cycling, contractility and cardiac myocyte metabolism. Several Na(+) transporters are electrogenic, thus they both contribute to shaping the cardiac action potential and at the same time are affected by it. [Na(+)]i is controlled by the balance between Na(+) influx through various pathways, including the Na(+)/Ca(2+) exchanger and Na(+) channels, and Na(+) extrusion via the Na(+)/K(+)-ATPase. [Na(+)]i is elevated in HF due to a combination of increased entry through Na(+) channels and/or Na(+)/H(+) exchanger and reduced activity of the Na(+)/K(+)-ATPase. Here we review the major Na(+) transport pathways in cardiac myocytes and how they participate in regulating [Na(+)]i in normal and failing hearts. This article is part of a Special Issue entitled "Na(+) Regulation in Cardiac Myocytes." PMID:23608603

Despa, Sanda; Bers, Donald M

2013-08-01

192

Neutron Multiplicity Discrimination in MoNA  

NASA Astrophysics Data System (ADS)

The Modular Neutron Array (MoNA) is a high-efficiency neutron detector at the National Superconducting Cyclotron Laboratory at MSU, used in conjunction with the NSCL/FSU sweeper magnet to investigate the loss of one or more neutrons from particle-unbound nuclei near and beyond the neutron drip-line. In order to properly analyze data from these experiments it is important to distinguish neutron multiplicity in MoNA. We've developed an algorithm that produces scatter plots of neutron velocity change vs. scattering angle and energy deposition vs. scattering angle, each of which results in a locus of events corresponding (largely) to single neutron multiple-scatter events, and each of which can be used to gate the other for cross-correlation. Challenges to accurate neutron trajectory mapping include sub-threshold neutron scattering from carbon (which changes neutron trajectories in unpredictable ways) and the discrete nature of the array, which (especially for shorter scattering lengths) results in scattering angles not necessarily reflective of actual neutron trajectories. Results for experiments involving one and two neutron decays will be presented.

Rogers, W. F.; Gillette, J.; Gardner, M.; Reed, A.; Mosby, S.

2007-10-01

193

CARACTERíSTICAS TECNOLÓGICAS DA FIBRA COM ÊNFASE NA FIABILlDADE DE CULTIVARES DE ALGODÃO HERBÁCEO DO MERCOSUL  

Microsoft Academic Search

RESUMO: Com o objetivo de se estudar as características tecnológicas da fibra, inclusive a fiabilidade de cultivares de algodão herbáceo (Gossypium hirsutum L. r. latifolium Hutch) cultivadas nos países do Mercosul, um ensaio internacional foi instalado no município de Ipanguaçu, RN, em 199.8, envolvendo dez cultivares provenientes da Argentina, Brasil, Bolívia e Paraguai. Quatorze características da fibra foram investigadas, sendo

FARIAS DE SANTANA; JOAQUIM NUNES DA COSTA; LUIZ PAULO DE CARVALH; ROBSON DE MACÊDO; JOSÉ EDILSON OLIVEIRA ANDRADE

194

Luminescence of NaCl:Tl and NaCl:In at high pressure  

SciTech Connect

The effects of pressure up to 40 kbar and temperatures down to 100 /sup 0/K on the intensity and lifetime of NaCa:Tl/sup +/ and NaCl:In has been studied. A kinetic model describing these luminescent properties has been proposed. The /sup 3/T/sub lu/ level is in thermal equilibrium with /sup 3/A/sub lu/. Both /sup 3/T/sub lu/ and /sup 3/A/sub lu/ have nonradiative pathways to the ground state /sup 1/A/sub lg/. In addition /sup 3/T/sub lu/ is radiatively coupled to the ground state. Increasing pressure increases the radiative rate from /sup 3/T/sub lu/ to /sup 1/A/sub lg/ and has no effect on the equilibrium between /sup 3/T/sub lu/ and /sup 3/A/sub lu/. The back feeding rate from /sup 3/A/sub lu/ to /sup 3/T/sub lu/ is temperature sensitive for NaCl:Tl but not for NaCl:In.

Littman, J.E.; Drickamer, H.G.

1982-03-01

195

Theoretical calculation of low-lying states of NaAr and NaXe  

NASA Technical Reports Server (NTRS)

Potential curves as well as dipole moments and linking transition moments are calculated for the ground X 2 Sigma + and low lying excited A 2 Pi, B 2 Sigma +, C 2 Sigma +, (4) 2 Sigma +, (2) 2 Pi and (1) 2 Delta states of NaAr and NaXe. Calculations are performed using a self-consistent field plus configuration-interaction procedure with the core electrons replaced by an ab initio effective core potential. The potential curves obtained are found to be considerably less repulsive than the semiempirical curves of Pascale and Vandeplanque (1974) and to agree well with existing experimental data, although the binding energies of those states having potential minima due to van der Waals interactions are underestimated. Emission bands are also calculated for the X 2 Sigma + - C 2 Sigma + excimer transitions of NaAr and NaXe using the calculated transition moments and potential curves, and shown to agree well with experiment on the short-wavelength side of the maximum.

Laskowski, B. C.; Langhoff, S. R.; Stallcop, J. R.

1981-01-01

196

Na-O Anticorrelation And HB I. The Na-O anticorrelation in NGC 2808  

E-print Network

We derived atmospheric parameters and elemental abundances of Fe, O and Na for about 120 red giant stars in the Galactic globular cluster NGC 2808. Our results are based on the analysis of medium-high resolution (R=22000-24000) GIRAFFE spectra acquired with the FLAMES spectrograph at VLT-UT2 as a part of a project aimed at studying the Na-O anticorrelation as a function of physical parameters in globular clusters. We present here the anticorrelation of Na and O abundances in NGC 2808, and we discuss the distribution function of stars along this relation. Besides a bulk of O-normal stars, with composition typical of field halo stars, NGC 2808 seems to host two other groups of O-poor and super O-poor stars. In this regard, NGC 2808 is similar to M 13, the template cluster for the Na-O anticorrelation. However, at variance with M 13, most stars in NGC 2808 are O-rich. This might be related to the horizontal branch morphologies which are very different in these two clusters. The average metallicity we found for NGC 2808 is [Fe/H]=-1.10 (rms=0.065 dex, from 123 stars). We also found some evidence of a small intrinsic spread in metallicity, but more definitive conclusions are hampered by the presence of a small differential reddening.

Eugenio Carretta; Angela Bragaglia; Raffaele Gratton; Francesco Leone; Alejandra Recio-Blanco; Sara Lucatello

2005-11-30

197

Na-O anticorrelation and HB. I. The Na-O anticorrelation in NGC 2808  

NASA Astrophysics Data System (ADS)

We derived the atmospheric parameters and elemental abundances of Fe, O, and Na for about 120 red giant stars in the Galactic globular cluster NGC 2808. Our results are based on the analysis of medium-high resolution (R=22 000{-}24 000) GIRAFFE spectra acquired with the FLAMES spectrograph at VLT-UT2 as a part of a project aimed at studying the Na-O anticorrelation as a function of physical parameters in globular clusters. We present the anticorrelation of Na and O abundances in NGC 2808 here, and discuss the distribution function of stars along this relation. Besides a bulk of O-normal stars with the typical composition of field halo stars, NGC 2808 seems to host two other groups of O-poor and super O-poor stars. In this regard, NGC 2808 is similar to M 13, the template cluster for the Na-O anticorrelation. However, in contrast to M 13, most stars in NGC 2808 are O-rich. This might be related to the horizontal branch morphologies that are very different in these two clusters. The average metallicity we found for NGC 2808 is [Fe/H]=-1.10 (rms = 0.065 dex, from 123 stars). We also found some evidence of a small intrinsic spread in metallicity, but more definitive conclusions are hampered by the presence of a small differential reddening.

Carretta, E.; Bragaglia, A.; Gratton, R. G.; Leone, F.; Recio-Blanco, A.; Lucatello, S.

2006-05-01

198

Minimizing Load Effects on NA4 Gear Vibration Diagnostic Parameter  

NASA Technical Reports Server (NTRS)

NA4 is a vibration diagnostic parameter, developed by researchers at NASA Glenn Research Center, for health monitoring of gears in helicopter transmissions. The NA4 reacts to the onset of gear pitting damage and continues to react to the damage as it spreads. This research also indicates NA4 reacts similarly to load variations. The sensitivity of NA4 to load changes will substantially affect its performance on a helicopter gearbox that experiences continuously changing load throughout its flight regimes. The parameter NA4 has been used to monitor gear fatigue tests at constant load. At constant load, NA4 effectively detects the onset of pitting damage and tracks damage severity. Previous research also shows that NA4 reacts to changes in load applied to the gears in the same way it reacts to the onset of pitting damage. The method used to calculate NA4 was modified to minimize these load effects. The modified NA4 parameter was applied to four sets of experimental data. Results indicate the modified NA4 is no longer sensitive to load changes, but remains sensitive to pitting damage.

Dempsey, Paula J.; Zakrajsek, James J.

2001-01-01

199

III Festival del Siglo de Oro (Chamizal)  

E-print Network

SPRING 1978 111 III Festival del Siglo de Oro (Chamizal) E. JARABA-PARDO El Siglo de Oro fue, por la fecundidad de los autores y por las influencias trascendentales de sus obras en el posterior desarrollo de la dramaturgia universal, uno de los... todos los actos de los hombres son guiados por Dios, quien se muestra como supremo hacedor de todo cuanto acontece a las criaturas. Se encuentran, pues, en síntesis en el teatro del Siglo de Oro unos valores particularmente antagónicos de la sociedad...

Jaraba-Pardo, E.

1978-04-01

200

NA Nonlinear Equation-of-state Inversion  

NASA Astrophysics Data System (ADS)

A fully non-linear inversion scheme is introduced for the determination of the parameters controlling the equation-of-state and elasticity of mineral phases using the thermodynamically consistent finite-strain formulation introduced by Stixrude & Lithgow-Bertelloni (2005). This inversion exploits a directed search in an eight-dimensional parameter space using the Neighbourhood Algorithm (NA) of Sambridge (1999) to search for the minimum of an objective function representing the misfit to multiple data sets that constrain different aspects of the mineral behaviour. No derivatives are employed and the progress towards the minimum builds on the accumulated information on the character of the parameter space acquired as the inversion progresses. When only a limited range of experimental information is available there is a strong possibility of multiple minima in the objective function, which can pose problems for conventional iterative least-squares or other gradient methods. The addition of many different styles of data tends to produce a better defined minimum. The influence of different data types can be readily assessed by allowing differential weighting. The new procedure is illustrated by application to MgO, for which extensive experimental data are available. These include the variation of relative volume V with temperature T and pressure P from both static and shock-compression experiments, acoustic measurements of compressional and shear (and hence bulk) moduli, and calorimetric determinations of entropy as a function of temperature at atmospheric pressure. Preliminary NA modeling highlighted tensions between marginally incompatible subsets of data. We therefore excluded one-atmosphere V(T) data for T ? 1800 K for which the quasi-harmonic approximation is inadequate (Wu et al., 2008) along with elastic moduli derived from Brillouin spectroscopy under conditions (P ? 14 GPa) where significant departures from hydrostatic conditions are expected. With these limited exclusions based on sound physical principles, the NA search identified a compact family of models that provide an excellent fit to the diverse experimental data and a measure of the covariance between key model parameters.

Jackson, I.; Kennett, B. L.

2008-12-01

201

Na?La?(CO?)? and CsNa?Ca?(CO?)?: two new carbonates as UV nonlinear optical materials.  

PubMed

Two nonlinear optical crystal carbonates (Na4La2(CO3)5 and CsNa5Ca5(CO3)8 were successfully synthesized by hydrothermal method, and both of them crystallized in the same noncentrosymmetric hexagonal space group P63mc (No. 186). The structure of Na4La2(CO3)5 consists of a three-dimensional network made up of [CO3] triangles as well as irregular [Na(0.67)La(0.33)O10] and [NaO8] polyhedra. The structure of CsNa5Ca5(CO3)8 can be described as the standing-on-edge [CO3] groups connect the adjacent infinite [CaCO3]? layers in the ab plane to construct a framework with four types of channels running parallel to [010]. The Na, Cs, and [Na(0.67)Ca(0.33)] atoms reside in these channels. The measurement of second harmonic generation (SHG) by the method adapted from Kurtz and Perry indicated that Na4La2(CO3)5 and CsNa5Ca5(CO3)8 were phase-matchable in the visible region and exhibited SHG responses of approximately 3 and 1 × KH2PO4 (KDP). Meanwhile, they exhibited wide transparent region with short UV cutoff edge at about 235 and 210 nm, respectively, suggesting that these crystals as NLO materials may have potential applications in the UV region. PMID:25027762

Luo, Min; Wang, GenXiang; Lin, Chensheng; Ye, Ning; Zhou, Yuqiao; Cheng, Wendan

2014-08-01

202

Ionic Liquid Electrolytes with Various Sodium Solutes for Rechargeable Na/NaFePO4 Batteries Operated at Elevated Temperatures.  

PubMed

NaFePO4 with an olivine structure is synthesized via chemical delithiation of LiFePO4 followed by electrochemical sodiation of FePO4. Butylmethylpyrrolidinium-bis(trifluoromethanesulfonyl)imide (BMP-TFSI) ionic liquid (IL) with various sodium solutes, namely NaBF4, NaClO4, NaPF6, and NaN(CN)2, is used as an electrolyte for rechargeable Na/NaFePO4 cells. The IL electrolytes show high thermal stability (>350 °C) and nonflammability, and are thus ideal for high-safety applications. The highest conductivity and the lowest viscosity of the electrolyte are obtained with NaBF4. At an elevated temperature (above 50 °C), the IL electrolyte is more suitable than a conventional organic electrolyte for the sodium cell. At 75 °C, the measured capacity of NaFePO4 in a NaBF4-incorporated IL electrolyte is as high as 152 mAh g(-1) (at 0.05 C), which is near the theoretical value (154 mAh g(-1)). Moreover, 60% of this capacity can be retained when the charge-discharge rate is increased to 1 C. PMID:25295391

Wongittharom, Nithinai; Wang, Chueh-Han; Wang, Yi-Chen; Yang, Cheng-Hsien; Chang, Jeng-Kuei

2014-10-22

203

El Servicio de Información sobre el Cáncer del Instituto Nacional del Cáncer  

Cancer.gov

El Servicio de Información del Cáncer (CIS) del Instituto Nacional del Cáncer facilita la información más actualizada y precisa sobre el cáncer a pacientes, a sus familias, al público en general y a profesionales médicos. El CIS brinda respuestas personalizadas a preguntas específicas sobre el cáncer y asistencia a los fumadores que quieren abandonar el hábito. Comuníquese con el CIS al 1-800-422-6237 (1-800-4-CANCER) o al 1-877-448-7848 (1-877-44U-QUIT).

204

Pyrophosphate-Fueled Na+ and H+ Transport in Prokaryotes  

PubMed Central

SUMMARY In its early history, life appeared to depend on pyrophosphate rather than ATP as the source of energy. Ancient membrane pyrophosphatases that couple pyrophosphate hydrolysis to active H+ transport across biological membranes (H+-pyrophosphatases) have long been known in prokaryotes, plants, and protists. Recent studies have identified two evolutionarily related and widespread prokaryotic relics that can pump Na+ (Na+-pyrophosphatase) or both Na+ and H+ (Na+,H+-pyrophosphatase). Both these transporters require Na+ for pyrophosphate hydrolysis and are further activated by K+. The determination of the three-dimensional structures of H+- and Na+-pyrophosphatases has been another recent breakthrough in the studies of these cation pumps. Structural and functional studies have highlighted the major determinants of the cation specificities of membrane pyrophosphatases and their potential use in constructing transgenic stress-resistant organisms. PMID:23699258

Malinen, Anssi M.; Luoto, Heidi H.

2013-01-01

205

Na+ transport in the normal and failing heart - remember the balance  

PubMed Central

In the heart, intracellular Na+ concentration ([Na+]i) is a key modulator of Ca2+ cycling, contractility and cardiac myocyte metabolism. Several Na+ transporters are electrogenic, thus they both contribute to shaping the cardiac action potential and at the same time are affected by it. [Na+]i is controlled by the balance between Na+ influx through various pathways, including the Na+/Ca2+ exchanger and Na+ channels, and Na+ extrusion via the Na+/K+-ATPase. [Na+]i is elevated in HF due to a combination of increased entry through Na+ channels and/or Na+/H+ exchanger and reduced activity of the Na+/K+-ATPase. Here we review the major Na+ transport pathways in cardiac myocytes and how they participate in regulating [Na+]i in normal and failing hearts. PMID:23608603

Despa, Sanda; Bers, Donald M.

2013-01-01

206

Cosmic Muon Tracking with MoNA  

NASA Astrophysics Data System (ADS)

The Modular Neutron Array (MoNA) consists of 144 2-meter long scintillating bar detectors arranged in a structure 9 bars deep and 16 bars high. Each detector has a photo-multiplier tube attached at each end, allowing for position determination of events based on timing difference. The array is housed at the National Superconducting Cyclotron Laboratory at Michigan State University and will be used to study exotic nuclei near the neutron dripline. The array is tested and calibrated using cosmic muons, and an algorithm has been developed to extract high multiplicity muon events from the datastream to enable precise tracking for use in position calibration of the detectors. This method represents a superior calibration procedure since in addition to correcting for differential time response between the PMTs at the ends of each bar, it also accounts for any relative physical misalignment of the detectors in the array.

Watters, Kyle; Elliott, Lance; Strongman, Michael; Rogers, Warren

2004-10-01

207

Lakota na Dakota Wowapi Oti Kin  

NSDL National Science Digital Library

The Lakota na Dakota Wowapi Oti Kin is a one-stop information portal containing Internet resources on people of Lakota and Dakota descent (also known as Sioux or Siouan peoples). Created and maintained by Professor Martin Brokenleg of Augustana College and Dr. Raymond Bucko, S.J. of Creighton University, this site offers Web links in various categories including art and artists / music and musicians, bibliographic resources, demography, education, history, language resources, legal issues, maps, museums, and a host of other Lakota-related sites. For those interested in locating information in the field of Native American studies, specifically on the Sioux peoples, this site is an excellent place to begin your search.

208

Representación y justicia en Manda patibularia de Santiago García  

E-print Network

el mundo. En efecto, a nivel nacional, la problemática del narcotráfico, de las cárceles de alta seguridad, y del llamado "Proceso 8000" relacionado con la infiltración de dinero proveniente del narcotráfico en la campaña presidencial de Ernesto...

Garavito, Lucí a

2001-04-01

209

Function of FXYD Proteins, Regulators of Na, K-ATPase  

Microsoft Academic Search

   In this short review, we summarize our work on the role of members of the FXYD protein family as tissue-specific modulators\\u000a of Na, K-ATPase. FXYD1 or phospholemman, mainly expressed in heart and skeletal muscle increases the apparent affinity for\\u000a intracellular Na+ of Na, K-ATPase and may thus be important for appropriate muscle contractility. FXYD2 or ? subunit and FXYD4 or

Käthi Geering

2005-01-01

210

Human myocardial Na,K-ATPase concentration in heart failure  

Microsoft Academic Search

The Na,K-ATPase is of major importance for active ion transport across the sarcolemma and thus for electrical as well as contractile function of the myocardium. Furthermore, it is receptor for digitalis glycosides. In human studies of the regulatory aspects of myocardial Na,K-ATPase concentration a major problem has been to obtain tissue samples. Methodological accomplishments in quantification of myocardial Na,K-ATPase using

Henning Bundgaard; Keld Kjeldsen

1996-01-01

211

Sodium superionic conduction in Na2B12H12.  

PubMed

Impedance measurements indicate that Na2B12H12 exhibits dramatic Na(+) conductivity (on the order of 0.1 S cm(-1)) above its order-disorder phase-transition at ?529 K, rivaling that of current, solid-state, ceramic-based, Na-battery electrolytes. Superionicity may be aided by the large size, quasispherical shape, and high rotational mobility of the B12H12(2-) anions. PMID:24584582

Udovic, Terrence J; Matsuo, Motoaki; Unemoto, Atsushi; Verdal, Nina; Stavila, Vitalie; Skripov, Alexander V; Rush, John J; Takamura, Hitoshi; Orimo, Shin-ichi

2014-04-11

212

Magnesium correction to the NaKCa chemical geothermometer  

USGS Publications Warehouse

Equations and graphs have been devised to correct for the adverse effects of magnesium upon the Na-K-Ca chemical geothermometer. Either the equations or graphs can be used to determine appropriate temperature corrections for given waters with calculated NaKCa temperatures > 70??C and R 50 are probably derived from relatively cool aquifers with temperatures approximately equal to the measured spring temperature, irrespective of much higher calculated Na-K-Ca temperatures. ?? 1979.

Fournier, R.O.; Potter, R.W., II

1979-01-01

213

Na+ interactions with the neutral amino acid transporter ASCT1.  

PubMed

The alanine, serine, cysteine transporters (ASCTs) belong to the solute carrier family 1A (SLC1A), which also includes the excitatory amino acid transporters (EAATs) and the prokaryotic aspartate transporter GltPh. Acidic amino acid transport by the EAATs is coupled to the co-transport of three Na(+) ions and one proton, and the counter-transport of one K(+) ion. In contrast, neutral amino acid exchange by the ASCTs does not require protons or the counter-transport of K(+) ions and the number of Na(+) ions required is not well established. One property common to SLC1A family members is a substrate-activated anion conductance. We have investigated the number and location of Na(+) ions required by ASCT1 by mutating residues in ASCT1 that correspond to residues in the EAATs and GltPh that are involved in Na(+) binding. Mutations to all three proposed Na(+) sites influence the binding of substrate and/or Na(+), or the rate of substrate exchange. A G422S mutation near the Na2 site reduced Na(+) affinity, without affecting the rate of exchange. D467T and D467A mutations in the Na1 site reduce Na(+) and substrate affinity and also the rate of substrate exchange. T124A and D380A mutations in the Na3 site selectively reduce the affinity for Na(+) and the rate of substrate exchange without affecting substrate affinity. In many of the mutants that reduce the rate of substrate transport the amplitudes of the substrate-activated anion conductances are not substantially affected indicating altered ion dependence for channel activation compared with substrate exchange. PMID:24808181

Scopelliti, Amanda J; Heinzelmann, Germano; Kuyucak, Serdar; Ryan, Renae M; Vandenberg, Robert J

2014-06-20

214

Kinetics of 9-aminoacridine block of single Na channels  

Microsoft Academic Search

The kinetics of 9-aminoacridine (9-AA) block of single Na chan- nels in neuroblastoma N 1 E-115 cells were studied using the gigohm seal, patch clamp technique, under the condition in which the Na current inactivation had been eliminated by treatment with N-bromoacetamide (NBA) . Following NBA treatment, the current flowing through individual Na channels was manifested by square-wave open events

DAISUKE YAMAMOTO; JAY Z. YEH

1984-01-01

215

CaMKII-dependent regulation of cardiac Na+ homeostasis  

PubMed Central

Na+ homeostasis is a key regulator of cardiac excitation and contraction. The cardiac voltage-gated Na+ channel, NaV1.5, critically controls cell excitability, and altered channel gating has been implicated in both inherited and acquired arrhythmias. Ca2+/calmodulin-dependent protein kinase II (CaMKII), a serine/threonine kinase important in cardiac physiology and disease, phosphorylates NaV1.5 at multiple sites within the first intracellular linker loop to regulate channel gating. Although CaMKII sites on the channel have been identified (S516, T594, S571), the relative role of each of these phospho-sites in channel gating properties remains unclear, whereby both loss-of-function (reduced availability) and gain-of-function (late Na+ current, INaL) effects have been reported. Our review highlights investigating the complex multi-site phospho-regulation of NaV1.5 gating is crucial to understanding the genesis of acquired arrhythmias in heart failure (HF) and CaMKII activated conditions. In addition, the increased Na+ influx accompanying INaL may also indirectly contribute to arrhythmia by promoting Ca2+ overload. While the precise mechanisms of Na+ loading during HF remain unclear, and quantitative analyses of the contribution of INaL are lacking, disrupted Na+ homeostasis is a consistent feature of HF. Computational and experimental observations suggest that both increased diastolic Na+ influx and action potential prolongation due to systolic INaL contribute to disruption of Ca2+ handling in failing hearts. Furthermore, simulations reveal a synergistic interaction between perturbed Na+ fluxes and CaMKII, and confirm recent experimental findings of an arrhythmogenic feedback loop, whereby CaMKII activation is at once a cause and a consequence of Na+ loading. PMID:24653702

Grandi, Eleonora; Herren, Anthony W.

2014-01-01

216

Mercury's Na Exosphere from MESSENGER Data  

NASA Technical Reports Server (NTRS)

MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UWS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft :0 infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The portion of the hot/cold source appears to be highly variable.

Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. El; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

2012-01-01

217

Questões mais freqüentes na área de astronomia  

NASA Astrophysics Data System (ADS)

É amplamente reconhecido que as pessoas em geral têm grande fascínio e interesse pela Astronomia. Por outro lado, o conteúdo dessa área incluído no ensino formal está longe de ser abrangente e suficiente para suprir a demanda. Esse interesse permite otimizar a divulgação e o ensino não formal de Astronomia aliando a adequação do conteúdo à expectativa das pessoas. Nesse intuito, nosso trabalho busca mapear que assuntos da Astronomia despertam mais a atenção e o interesse das pessoas e o quanto disso é estimulado pela mídia, que freqüentemente aproveita-se desse interesse de forma sensacionalista, trazendo contribuições positivas e negativas. Para esta avaliação, utilizamos as pesquisas específicas e de caracterização do público que freqüentou o MAst nos anos de 2001 a 2003, pesquisa das matérias de Astronomia veiculadas na mídia escrita da cidade do Rio de Janeiro no mesmo período, além da base de dados do programa Pergunte a um astrônomo, realizado no Observatório Nacional nos anos de 1997 a 1999. Para a análise dos dados, dividimos as perguntas em dez categorias, cada uma com suas subcategorias, tomando como referência as divisões, comissões e grupos de trabalho da IAU. Apresentamos neste trabalho os resultados dessa pesquisa, que incluem, entre outros, a predominância de questões nas categorias Observação do Céu e Sistemas Planetários enquanto nos jornais dominam as notícias de Sistemas Planetários e Espaço & Astronáutica. Outro resultado interessante indicou que as dúvidas de crianças do ensino fundamental se concentram em algumas categorias enquanto as questões de adultos são mais distribuídas por todas as categorias. Os resultados dessa pesquisa serão aplicados diretamente no aperfeiçoamento das atividades do Programa de Observação de Céu, bem como na elaboração de novos projetos e eventos realizados no MAst.

Segundo, H. A. S.; Garcia, G. C.; Caretta, C. A.; Lima, F. P.

2003-08-01

218

UN REGALO PARA HISTORIA. A CMERA DE UM "TIGRE DO SAARA" RETRATA TEMPOS DE ESCURIDO NA REPBLICA ORIENTAL DEL URUGUAY.  

E-print Network

-chave: Ditadura no Uruguai, História e Jornalismo, Jornalismo de Oposição, Exílio Político. #12;Cinco de maio de contrária à ditadura instaurada pelo Generalíssimo Francisco Franco presentearam o jornalismo latino

Paris-Sud XI, Université de

219

La reconstrucción del seno después de una mastectomía  

Cancer.gov

Hoja informativa que describe la reconstrucción del seno (mama) después de una mastectomía. Contiene información sobre las opciones quirúrgicas, los cuidados de seguimiento y los exámenes de detección del cáncer de seno después de la reconstrucción.

220

A novel missense mutation in SLC34A3 that causes hereditary hypophosphatemic rickets with hypercalciuria in humans identifies threonine 137 as an important determinant of sodium-phosphate cotransport in NaPi-IIc.  

PubMed

The present study describes two novel compound heterozygous mutations, c.410C>T(p.T137M) (T137M) on the maternal and g.4225_50del on the paternal allele of SLC34A3, in a previously reported male with hereditary hypophosphatemic rickets with hypercalciuria (HHRH) and recurrent kidney stones (Chen C, Carpenter T, Steg N, Baron R, Anast C. Pediatrics 84: 276-280, 1989). For functional analysis in vitro, we generated expression plasmids encoding enhanced green fluorescence protein (EGFP) concatenated to the NH2 terminus of wild-type or mutant human type IIc Na-Pi cotransporter (NaPi-IIc), i.e., EGFP-hNaPi-IIc, EGFP-[M137]hNaPi-IIc, or EGFP-[Stop446]hNaPi-IIc. The V446Stop mutant showed complete loss of expression and function when assayed for apical patch expression in opossum kidney (OK) cells and sodium-dependent 33P uptake into Xenopus laevis oocytes. Conversely, EGFP-[M137]hNaPi-IIc was inserted into apical patches of OK cells and into oocyte membranes. However, when quantified by confocal microscopy, surface fluorescence was reduced to 40% compared with wild-type. After correction for surface expression, the rate of 33P uptake by oocytes mediated by EGFP-[M137]hNaPi-IIc was decreased by an additional 60%. The resulting overall reduction of function of this NaPi-IIc mutant to 16%, taken together with complete loss of expression and function of g.4225_50del(V446Stop), thus appears to be sufficient to explain the phenotype in our patient. Furthermore, the stoichiometric ratio of 22Na and 33P uptake was increased to 7.1 +/- 3.65 for EGFP-[M137]hNaPi-IIc compared with wild-type. Two-electrode studies indicate that EGFP-[M137]hNaPi-IIc is nonelectrogenic but displayed a significant phosphate-independent inward-rectified sodium current, which appears to be insensitive to phosphonoformic acid. M137 thus may uncouple sodium-phosphate cotransport, suggesting that this amino acid residue has an important functional role in human NaPi-IIc. PMID:18480181

Jaureguiberry, Graciana; Carpenter, Thomas O; Forman, Stuart; Jüppner, Harald; Bergwitz, Clemens

2008-08-01

221

Kaolin-based geopolymers with various NaOH concentrations  

NASA Astrophysics Data System (ADS)

Kaolin geopolymers were produced by the alkali-activation of kaolin with an activator solution (a mixture of NaOH and sodium silicate solutions). The NaOH solution was prepared at a concentration of 6-14 mol/L and was mixed with the sodium silicate solution at a Na2SiO3/NaOH mass ratio of 0.24 to prepare an activator solution. The kaolin-to-activator solution mass ratio used was 0.80. This paper aimed to analyze the effect of NaOH concentration on the compressive strength of kaolin geopolymers at 80°C for 1, 2, and 3 d. Kaolin geopolymers were stable in water, and strength results showed that the kaolin binder had adequate compressive strength with 12 mol/L of NaOH concentration. When the NaOH concentration increased, the SiO2/Na2O decreased. The increased Na2O content enhanced the dissolution of kaolin as shown in X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses. However, excess in this content was not beneficial for the strength development of kaolin geopolymers. In addition, there was the formation of more geopolymeric gel in 12 mol/L samples. The XRD pattern of the samples showed a higher amorphous content and a more geopolymer bonding existed as proved by FTIR analysis.

Heah, C. Y.; Kamarudin, H.; Mustafa Al Bakri, A. M.; Bnhussain, M.; Luqman, M.; Khairul Nizar, I.; Ruzaidi, C. M.; Liew, Y. M.

2013-03-01

222

Reconstitution of a bacterial Na+/H+ antiporter  

SciTech Connect

Membrane proteins from alkalophilic Bacillus firmus RAB were extracted with octylglucoside, reconstituted into liposomes made from alkalophile lipids. The proteoliposomes were loaded with SSNa . Imposition of a valinomycin-mediated potassium diffusion potential, positive out, resulted in very rapid efflux of radioactive Na against its electrochemical gradient. That the Na efflux was mediated by the electrogenic Na /H antiporter is indicated by the following characteristics that had been established for the porter in previous studies: dependence upon an electrical potential; pH sensitivity, with activity dependent upon an alkaline pH; inhibition by Li ; and an apparent concentration dependence upon Na that correlated well with measurements in cells and membrane vesicles.

Seto-Young, D.; Garcia, M.L.; Krulwich, T.A.

1985-09-25

223

Association reactions of Na(+) and some implications for interstellar chemistry  

NASA Astrophysics Data System (ADS)

Three-body association reactions of Na+ with a variety of neutral gases in the presence of He as third body have been studied in a Selected Ion Flow Tube at 80K. The measured rate coefficients have been utilized to estimate radiative association rate coefficients at 20K. It is shown that Na+-neutral radiative association reactions play a role in the depletion of Na+ in dense interstellar clouds and can produce a sufficient amount of NaOH to explain its observed tentative abundance in Sgr B2.

Smith, D.; Adams, N. G.; Alge, E.; Herbst, E.

1983-09-01

224

Research in Automated Reasoning Alvaro del Val  

E-print Network

Research in Automated Reasoning Alvaro del Val E.T.S. Inform´atica Universidad Aut´onoma de Madrid, and then using reasoning algorithms to extract consequences from that knowledge. Knowledge representation deals with the issue of defining languages suitable for various domains and reasoning tasks; automated reasoning

Autonoma de Madrid, Universidad

225

GEOGRAFAAGRARIA (1 parte del Tema 1)  

E-print Network

;Diferenciación de los paisajes agrarios Usos del suelo Técnicas de riego empleadas Formas y tamaños de las (suelos y climas), biológicos (cultivos) y culturales sobre un espacio económico no urbano de la

Escolano, Francisco

226

Le origini del mondo Giuseppe Longo  

E-print Network

Bang: T= 0 (17.000.000.000 anni fa) La storia di una lenta morte termica ? L'energia totale dell ogni grandezza fisica Q diminuisce con il volume V R età = t 1/R3 1/t3 La densità di energia #12;Le origini #12;Formazione del sistema solare storia Geologia Fisica Chimica Biologia Fisica dell

Santorelli, Pietro

227

ECONOMÍAS EXTERNAS Y LOCALIZACIÓN DEL EMPLEO INDUSTRIAL  

Microsoft Academic Search

Es un hecho fácilmente constatable que la actividad económica en gene- ral e industrial en particular se localiza de forma desigual a lo largo de la geografía española. El presente trabajo plantea un modelo que tiene como objetivo analizar la incidencia de las economías externas en la dis- tribución territorial del empleo de los distintos sectores industriales. El modelo incorpora

ELISABET VILADECANS MARSAL

2003-01-01

228

MINOR DE COMPUTACION CIENTIFICA Nombre del Minor  

E-print Network

SCT CC3001 Algoritmos y estructuras de datos 10 FI3104 Métodos numéricos para la ciencia e ingeniería. Código Nombre CC3001 Algoritmos y estructuras de datos Nombre en Inglés Algorithms and data structures Aprendizaje Al termino del curso se espera que el estudiante conozca, aplique y analice las estructuras de

Rapaport, Iván

229

SPTIMA EDICIN Del 18 de marzo al  

E-print Network

de Seguridad de la Universidad Rey Juan Carlos. Profesor: D. Daniel Campos Navas. Fiscal de la Seguridad. CTC 3. Caso práctico Profesor: D. Andrés Martínez Calvo. Secretaría General delTesoro y Política

Rey Juan Carlos, Universidad

230

Uso Eficiente del Agua en Ingenios Azucareros  

Microsoft Academic Search

El impacto que produce el alto consumo de agua en regiones donde este recurso es limitado, alienta al desarrollo de nuevas técnicas que permitan analizar la administración eficiente del agua en las industrias y que comúnmente se concreta realizando balances detallados para diferentes configuraciones propuestas de uso de agua. En este trabajo se presenta una metodología alternativa, mediante el cálculo

Alejandra Ingaramo; Humberto Heluane; Mauricio Colombo; Tomás Argüello; Mario Cesca

231

Exámenes selectivos de detección del cáncer colorrectal  

Cancer.gov

Un ejemplo excelente del poder de la investigación de prevención es el progreso sustancial que hemos logrado en la reducción de la incidencia y muerte por cáncer colorrectal, con nuevos conocimientos que iluminan el camino a incluso mayores reducciones en un futuro cercano.

232

Facultad de Derecho DATOS DEL ALUMNO  

E-print Network

Facultad de Derecho DATOS DEL ALUMNO APELLIDOS 1º 2º NOMBRE NIF DIRECCI�N LOCALIDAD CP PROVINCIA EMAIL TFNO. FIJO TFNO. MOVIL IMPORTANTE Para obtener los correspondientes títulos de Derecho y ADE, el elección, con los siguientes requisitos: - Los créditos de libre elección necesarios son 30,5 para Derecho

Escolano, Francisco

233

Hereditary hypophosphatemic rickets with hypercalciuria and nephrolithiasis-identification of a novel SLC34A3/NaPi-IIc mutation.  

PubMed

Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is characterized by rickets, hyperphosphaturia, hypophosphatemia, elevated 1,25-dihydroxyvitamin-D, increased gastrointestinal calcium absorption and hypercalciuria. Serum calcium, 25-hydroxyvitamin-D and PTH levels are normal. Here we describe a boy with HHRH, nephrolithiasis, and compound heterozygosity for one previously described mutation (g.4225_50del) and a novel splice mutation (g.1226G>A) in SLC34A3, the gene encoding the renal sodium-phosphate co-transporter NaPi-IIc. The patient's mother and grandmother are carriers of g.4225_50del, and both have a history of nephrolithiasis associated with hypercalciuria and elevated 1,25-dihydroxyvitamin-D. His three siblings (2-6 years old), who are also carriers of g.4225_50del, have hypercalciuria but so far their renal ultrasounds are normal. Thus, SLC34A3/NaPi-IIc mutations appear to be associated with variable phenotypic changes at presentation, which can include recurrent nephrolithiasis. PMID:21344632

Phulwani, Priya; Bergwitz, Clemens; Jaureguiberry, Graciana; Rasoulpour, Majjid; Estrada, Elizabeth

2011-03-01

234

Use of Na-Nuclear Magnetic Resonance To Follow Sodium Uptake and Efflux in NaCl-Adapted and Nonadapted Millet (Panicum miliaceum) Suspensions.  

PubMed

Cellular Na(+) transport was followed in vivo by (23)Na nuclear magnetic resonance (NMR) using anionic dysprosium-based shift reagents to resolve internal and external (23)Na(+) resonances. Proso millet (Panicum miliaceum) cell suspensions adapted for rapid growth on 130 mm NaCl had biphasic (23)Na efflux kinetics when shifted to low Na(+) medium, while nonadapted cells had little measurable Na(+) efflux after preloading with (23)NaCl. Uptake of (23)Na was also observed using (23)Na NMR. The resonance frequency of the external Na(+)-dysprosium (III) triphosphate, relative to that of the (23)Na in the cells, was sensitive to pH, permitting the pH of the external medium to be followed during the course of in vivo experiments. PMID:16663592

Sillerud, L O; Heyser, J W

1984-05-01

235

Use of /sup 23/Na-nuclear magnetic resonance to follow sodium uptake and efflux in NaCl-adapted and nonadapted millet (Panicum miliaceum) suspensions  

SciTech Connect

Cellular Na/sup +/ transport was followed in vivo by /sup 23/Na nuclear magnetic resonance (NMR) using anionic dysprosium-based shift reagents to resolve internal and external /sup 23/Na/sup +/ resonances. Proso millet (Panicum miliaceum) cell suspensions adapted for rapid growth on 130 mM NaCl had biphasic /sup 23/Na efflux kinetics when shifted to low Na..mu.. medium, while nonadapted cells had little measurable Na/sup +/ efflux after preloading with /sup 23/NaCl. Uptake of /sup 23/Na was also observed using /sup 23/Na NMR. The resonance frequency of the external Na/sup +/-dysprosium (III) triphosphate, relative to that of the /sup 23/Na in the cells, was sensitive to pH, permitting the pH of the external medium to be followed during the course of in vivo experiments. 20 references, 3 figures.

Sillerud, L.O.; Heyser, J.W.

1984-05-01

236

Electrode potential studies of liquid-solid equilibrium in Na{sub 3}Bi-saturated Na-Bi melts  

SciTech Connect

Liquid binary Na-Bi alloys have been studied extensively because of the interest in possible uses as electrochemically active couples in regenerative electrochemical cells, in high-energy batteries, and as potential heat-transfer media in nuclear reaction processes. Techniques used previously for thermodynamic measurements on the system have included the transpiration method, quasi-static and boiling point methods, the electromotive force (emf) method using molten salt mixtures and various solid electrolytes, and thermal analysis. Most of the thermodynamic data on Bi-Na alloys were recently assessed by Sangster and Pelton. However, no experimental thermodynamic data for liquid-solid equilibrium in liquid Na-Bi alloys saturated with solid Na{sub 3}Bi have been reported in the literature. The aim of the present work was to investigate experimentally the equilibrium between Na-Bi melts and solid Na{sub 3}Bi by the emf method in the range 638 to 973 K.

Yan, X.Y.; Langberg, D.E.; Rankin, W.J.

2000-04-01

237

Boletín del Instituto Nacional del Cáncer - 22 de mayo de 2012  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

238

Boletín del Instituto Nacional del Cáncer - 19 de julio de 2011  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

239

Boletín del Instituto Nacional del Cáncer - 24 de abril de 2012  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

240

Boletín del Instituto Nacional del Cáncer - 11 de octubre de 2011  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

241

Boletín del Instituto Nacional del Cáncer - 8 de noviembre de 2011  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

242

Boletín del Instituto Nacional del Cáncer - 27 de marzo de 2012  

Cancer.gov

Le invitamos a que comparta esta publicación con sus amigos, familiares y colegas y nos ayude a continuar nuestra misión de difundir las investigaciones más recientes sobre la prevención, el tratamiento y la información del cáncer.

243

Mechanism of ?-Conotoxin PIIIA Binding to the Voltage-Gated Na+ Channel NaV1.4  

PubMed Central

Several subtypes of voltage-gated Na+ (NaV) channels are important targets for pain management. ?-Conotoxins isolated from venoms of cone snails are potent and specific blockers of different NaV channel isoforms. The inhibitory effect of ?-conotoxins on NaV channels has been examined extensively, but the mechanism of toxin specificity has not been understood in detail. Here the known structure of ?-conotoxin PIIIA and a model of the skeletal muscle channel NaV1.4 are used to elucidate elements that contribute to the structural basis of ?-conotoxin binding and specificity. The model of NaV1.4 is constructed based on the crystal structure of the bacterial NaV channel, NaVAb. Six different binding modes, in which the side chain of each of the basic residues carried by the toxin protrudes into the selectivity filter of NaV1.4, are examined in atomic detail using molecular dynamics simulations with explicit solvent. The dissociation constants (Kd) computed for two selected binding modes in which Lys9 or Arg14 from the toxin protrudes into the filter of the channel are within 2 fold; both values in close proximity to those determined from dose response data for the block of NaV currents. To explore the mechanism of PIIIA specificity, a double mutant of NaV1.4 mimicking NaV channels resistant to ?-conotoxins and tetrodotoxin is constructed and the binding of PIIIA to this mutant channel examined. The double mutation causes the affinity of PIIIA to reduce by two orders of magnitude. PMID:24676211

Chen, Rong; Robinson, Anna; Chung, Shin-Ho

2014-01-01

244

Enhancement of the sulfur capture capacity of limestones by the addition of Na2CO3 and NaCl.  

PubMed

The ability of Na2CO3 and NaCl to enhance the sulfur capture capacity of three limestones was evaluated via fixed-bed calcination and sulfation experiments. The tested limestones represent three different sulfation morphologies: unreacted-core, network, and uniformly sulfated. Treatment with aqueous or powdered Na2CO3 significantly increased the Ca-utilization for two stones which normally sulfate in an unreacted-core pattern (20% to 45%) and network pattern (33% to 49%). The increase was lower for the uniformly sulfated stone (44% to 48%). Na2CO3 treatment increased the number of macropores leading to uniform sulfation of all particles, nearly eliminating the normal strong dependence of utilization on limestone type and particle size. The effect of Na2CO3 is believed to be associated with formation of a eutectic melt which enhances ionic diffusion and accelerates molecular rearrangement of the CaO. Treatment with aqueous NaCl solution caused a decrease in utilization, probably due to formation of large grains and plugging of pores caused by formation of a large amount of eutectic melt. The effect of Na2CO3 is less sensitive than that of NaCl to the amount added and the combustion environment (temperature and gas composition). In addition, Na2CO3 neither promotes corrosion nor forms chlorinated byproducts, which are main concerns associated with NaCl. Thus, Na2CO3 appears to have significant advantages over NaCl for enhancement of limestone sulfur capture capacity in fluidized-bed combustors. PMID:11718362

Laursen, K; Grace, J R; Lim, C J

2001-11-01

245

RNA adducts with Na 2SeO 4 and Na 2SeO 3 - Stability and structural features  

NASA Astrophysics Data System (ADS)

Selenium compounds are widely available in dietary supplements and have been extensively studied for their antioxidant and anticancer properties. Low blood Se levels were found to be associated with an increased incidence and mortality from various types of cancers. Although many in vivo and clinical trials have been conducted using these compounds, their biochemical and chemical mechanisms of efficacy are the focus of much current research. This study was designed to examine the interaction of Na 2SeO 4 and Na 2SeO 3 with RNA in aqueous solution at physiological conditions, using a constant RNA concentration (6.25 mM) and various sodium selenate and sodium selenite/polynucleotide (phosphate) ratios of 1/80, 1/40, 1/20, 1/10, 1/5, 1/2 and 1/1. Fourier transform infrared, UV-Visible spectroscopic methods were used to determine the drug binding modes, the binding constants, and the stability of Na 2SeO 4 and Na 2SeO 3-RNA complexes in aqueous solution. Spectroscopic evidence showed that Na 2SeO 4 and Na 2SeO 3 bind to the major and minor grooves of RNA ( via G, A and U bases) with some degree of the Se-phosphate (PO 2) interaction for both compounds with overall binding constants of K(Na 2SeO 4-RNA) = 8.34 × 10 3 and K(Na 2SeO 3-RNA) = 4.57 × 10 3 M -1. The order of selenium salts-biopolymer stability was Na 2SeO 4-RNA > Na 2SeO 3-RNA. RNA aggregations occurred at higher selenium concentrations. No biopolymer conformational changes were observed upon Na 2SeO 4 and Na 2SeO 3 interactions, while RNA remains in the A-family structure.

Nafisi, Shohreh; Manouchehri, Firouzeh; Montazeri, Maryam

2011-12-01

246

Conductance and gating of epithelial Na channels from rat cortical collecting tubule. Effects of luminal Na and Li  

Microsoft Academic Search

The behavior of individual Na channels in the apical membrane of the rat cortical collecting tubule (CCT) was studied at different concentrations of the permeant ions Na and Li. Tubules were opened to expose their luminal sur- faces and bathed in K-gluconate medium to minimize tubule-to-tubule variation in cell membrane potential and intracellular Na concentration. The patch-clamp technique was used

LAWRENCE G. PALMER; GUSTAVO FRINDT

1988-01-01

247

Crnica I Encontro Solar na UDC O pasado mrcores 24 de abril tivo lugar na Praza da Fraga (Campus da  

E-print Network

/informativos/os-universitarios-da-coruna-comparten-unha-xornada-de- gastronomia-solar-573783 http://www.lavozdegalicia.es/noticia/coruna/2013/04/24/cocina-universitaria-energiaCr�nica I Encontro Solar na UDC O pasado m�rcores 24 de abril tivo lugar na Praza da Fraga (Campus da Zapateira) a primeira edici�n do Encontro Solar na UDC. Esta era a terceira das actividades

Fraguela, Basilio B.

248

Solubility of MgO in MgCl{sub 2}-NaCl-NaF melts  

SciTech Connect

The solubility of MgO in MgCl{sub 2}-NaCl-NaF melts has been measured for melts with varying NaF concentration for x{sub MgCl{sub 2}} = 0.10 and 0.63 and for x{sub MgCl{sub 2}}/x{sub NaCl} = 1.70. Melt samples have been analyzed by carbothermal reduction (Leco TC-436) for total oxide content. The oxide content in the binary melt MgCl{sub 2}-NaCl was also analyzed by Iodometric titration. The results indicate two different oxide-containing species, denoted MgOCl and MgOF, in the solidified samples withdrawn from the melt. The latter appears only in fluoride-containing melts, but may, however, also contain chloride ions. The oxide solubility is increasing with increasing concentration of Mg{sup 2+} in both MgCl{sub 2}-NaCl and MgCl{sub 2}-NaCl-NaF melts. The solubility of MgO is always higher in fluoride containing melts at the same Mg{sup 2+} concentration. In the systems concentrated in MgCl{sub 2}, the increase in oxide solubility as function of x{sub NaF} is more pronounced than what is predicted from a simple model calculation. The increase is much smaller in the x{sub NaF} < 0.2 range for small MgCl{sub 2} contents than predicted from the same model calculation. The introduction of 1.7 mol% NaF to an industrial electrolyte does not seem to change the oxide solubility significantly. In such an electrolyte, where x{sub MgCl{sub 2}} {approx_equal} 0.1, the data gives a constant oxide solubility around 10 ppm O up to 5 mol% NaF.

Mediaas, H.; Vinstad, J.E.; Oestvold, T. [Norwegian Inst. of Tech., Trondheim (Norway). Inst. of Inorganic Chemistry

1996-10-01

249

Propagac ~ao acustica em aguas profundas na presenca de massas d'aguas de mesoescala na costa sudoeste de Portugal  

E-print Network

Propagac¸ ~ao ac´ustica em ´aguas profundas na presenc¸a de massas d'´aguas de mesoescala na costa trabalho baseia-se no estudo da propagac¸ ~ao sonora em ´aguas oce^anicas profundas na costa Portuguesa massa d'´agua de mesosescala. Mostraremos que tal massa d'´agua d´a origem `a um acoplamento entre dois

Jesus, Sérgio M.

250

Crecimiento del PIB vs. Consumo de Energa (variacin % respecto del ao base 1990)  

E-print Network

2 3 4 #12;5 Crecimiento del PIB vs. Consumo de Energía (variación % respecto del año base 1990) 0 Coal Nuclear Energy Hydro electric 16 #12;17 Venezuela Santiago Existing pipeline Planned pipeline% Diesel-fuel oil 13% Hydro 39% Natural gas 36% Coal 18% Others 2% Diesel-fuel oil 5% 19 Sistema MW % SING

Catholic University of Chile (Universidad Católica de Chile)

251

Boletín del Instituto Nacional del Cáncer - 31 de enero de 2012  

Cancer.gov

Dr. Nils Daulaire Salud mundial a través de la colaboración y el liderazgo Para conmemorar el Día Mundial del Cáncer que tuvo lugar el 4 febrero, el doctor Nils Daulaire, director de la Oficina de Asuntos Internacionales del Departamento de Salud y Servicios Humanos de los Estados Unidos habla sobre las razones por las cuales los Estados Unidos deben participar en iniciativas para mejorar la salud mundial.

252

Análisis del Proceso Software Basado en Modelos de Producción Industrial  

Microsoft Academic Search

La modelización del Proceso Software constituye un marco de referencia para la organización de las actividades que involucran todas las etapas del desarrollo, tendente a la resolución de problemas que el propio desarrollo de software plantea y genera a medida que evoluciona. La modelización del proceso se hace mas compleja a medida que el desarrollo tecnológico, metodológico y, fundamentalmente la

Alicia Mon

253

Lecturas sobre derecho del medio ambiente t. IV  

Microsoft Academic Search

Explorando los algunos aspectos vulnerables del derecho del medio ambiente, se tratan, entre otros, las responsabilidades civiles de aquellos que menoscaban nuestro hábitat, y del aseguramiento que se debe tener para el transporte y almacenamiento de desechos peligrosos, no solo a la luz de la legislación colombiana, sino de la argentina, chilena y española.

Autores varios

254

Piano Lauree Scientifiche: Aspetti matematici del Rudiger Achilles  

E-print Network

Bologna, 3 Febbraio 2014 3 / 19 #12;GPS III SATELLITE Piano Lauree Scientifiche: Aspetti matematici delPiano Lauree Scientifiche: Aspetti matematici del GPS R¨udiger Achilles Universit`a di Bologna Bologna, 3 Febbraio 2014 Piano Lauree Scientifiche: Aspetti matematici del GPS R¨udiger Achilles Bologna

Achilles, Rüdiger

255

Economía del narcotráfico, Plan Colombia y conflicto interno en Colombia  

Microsoft Academic Search

El artículo presenta una semblanza del entorno político reciente que compromete una dimensión de las estrategias de la lucha contra las drogas; un mapa del mercado de narcóticos, especialmente centrado en el de cocaina; los fundamentos de la estrategia de lucha contra el narcotráfico y los elementos de su crísis; la dimensión del Negocio de la cocaína, considerando una cuantificación

Olmedo Vargaz Hernández

2005-01-01

256

EDITORIAL: TaCoNa-Photonics 2008 TaCoNa-Photonics 2008  

Microsoft Academic Search

This special section on theoretical and computational nano-photonics features papers presented at the first International Workshop on Theoretical and Computational Nano-Photonics (TaCoNa-Photonics 2008) held in Bad Honnef, Germany, 3-5 December 2008. The workshop covered a broad range of topics related to current developments and achievements in this interdisciplinary area of research. Since the late 1960s, the word `photonics' has been

Dmitry N. Chigrin; Kurt Busch; Andrei V. Lavrinenko

2009-01-01

257

Central role of the Na+-translocating NADH:quinone oxidoreductase (Na+-NQR) in sodium bioenergetics of Vibrio cholerae.  

PubMed

Abstract Vibrio cholerae is a Gram-negative bacterium that lives in brackish or sea water environments. Strains of V. cholerae carrying the pathogenicity islands infect the human gut and cause the fatal disease cholera. Vibrio cholerae maintains a Na+ gradient at its cytoplasmic membrane that drives substrate uptake, motility, and efflux of antibiotics. Here, we summarize the major Na+-dependent transport processes and describe the central role of the Na+-translocating NADH:quinone oxidoreductase (Na+-NQR), a primary Na+ pump, in maintaining a Na+-motive force. The Na+-NQR is a membrane protein complex with a mass of about 220 kDa that couples the exergonic oxidation of NADH to the transport of Na+ across the cytoplasmic membrane. We describe the molecular architecture of this respiratory complex and summarize the findings how electron transport might be coupled to Na+-translocation. Moreover, recent advances in the determination of the three-dimensional structure of this complex are reported. PMID:25205724

Steuber, Julia; Halang, Petra; Vorburger, Thomas; Steffen, Wojtek; Vohl, Georg; Fritz, Günter

2014-12-01

258

Estimating the hydrogen ion concentration in concentrated NaCl and Na{sub 2}SO{sub 4} electrolytes  

SciTech Connect

Combination glass electrodes were tested for determining H{sup +} concentrations in concentrated pure and mixed NaCl and Na{sub 2}SO{sub 4} solutions, as well as natural brine systems. NaCl, Na{sub 2}SO{sub 4}, and mixtures of NaCl and Na{sub 2}SO{sub 4} solutions were analyzed. Correction factors for estimating pC{sub H}{sup +} (negative logarithm of H{sup +} concentration) were determined from measured/observed pH values. Required Gran-type titrations were done with HCl and/or NaOH. The titration method is described and a step-by-step procedure provided; it has been used previously for determining pC{sub H}{sup +} values of synthetic chloride-dominated brines. Precautions are required to determine correction factors for electrolytes that react with H{sup +} or OH{sup {minus}} [sulfate brines for titration with acid; magnesium brines for titration with base because of precipitation of Mg(OH)2]. Correction factors A (pC{sub H}{sup +} = pH{sub ob} + A) from HCl titrations were similar to those from NaOH titrations where the concentration of free H{sup +} was calculated using a thermodynamic model. These values should be applicable to solns with a very large range in measured pH values (2 to 12). Because a large number of solns were titrated with HCl and the A values are similar for HCl and NaOH titrations, the A values for NaCl and Na2SO4 solns were fit as a function of molality to allow extrapolation. For NaCl solns 0 to 6.0 M, A can be obtained by multiplying the molality by 0.159. For Na2SO4 solns 0 to 2.0 M, the values of A can be obtained from (0.221 {minus} 0.549X + 0.201X{sup 2}), where X is the molality of Na{sub 2}SO{sub 4}. Orion-Ross electrode evaluations indicated that the A values did not differ significantly for different electrodes. Results suggest that the data in this report can be used to estimate A values for different NaCl and Na{sub 2}SO{sub 4} solns even for noncalibrated electrodes.

Rai, D.; Felmy, A.R.; Juracich, S.P.; Rao, F. [Pacific Northwest Lab., Richland, WA (United States)

1995-06-01

259

Estructura y paleogeografa de los materiales del Trisico en la terminacin meridional del Arco de Cazorla (Jan, Cordillera  

E-print Network

243 Estructura y paleogeografía de los materiales del Triásico en la terminación meridional del relleno de la cuenca del Guadalquivir. La dirección de la ma- yor parte de las estructuras en la Sierra de del Arco y sobre la evolución de esta gran estructura, donde existen importantes accidentes que delimi

Herrera, Carlos M.

260

Publicaciones del IGME: serie Hidrogeologa y aguas subterrneas, n 14. VI Simposio del Agua en Andaluca. I: 669-678  

E-print Network

Publicaciones del IGME: serie Hidrogeología y aguas subterráneas, nº 14. VI Simposio del Agua en Andalucía. I: 669-678 Problemática de la calidad de las aguas de la Vega de Granada para el riego del tabaco Castillo Martín, Antonio* y Sánchez Díaz, Luis** * CSIC e Instituto del Agua de la Universidad de Granada

Castillo, Antonio

261

Estudio para la prevención del cáncer necesita voluntarias: El Estudio del Tamoxifeno y Raloxifeno (STAR) se realiza en Norteamérica  

Cancer.gov

El Estudio del Tamoxifeno y Raloxifeno (STAR, por sus siglas en inglés), uno de los estudios más importantes realizados para la prevención del cáncer del seno, está ahora reclutando voluntarias en más de 400 centros en los Estados Unidos, Puerto Rico y Canadá.

262

Anatomia delle componenti ossee dell'ATM; Anatomia del disco articolare;  

E-print Network

· Anatomia delle componenti ossee dell'ATM; · Anatomia del disco articolare; · Anatomia del tessuto retrodiscale; · Anatomia dei legamenti capsulari ed extra capsulari; · Anatomia del muscolo; · Anatomia del nervo trigemino; · Anatomia del nervo facciale; · Anatomia del nervo ipoglosso

Di Pillo, Gianni

263

Cryptography in NaCl Daniel J. Bernstein  

E-print Network

Cryptography in NaCl Daniel J. Bernstein Department of Computer Science (MC 152) The University against espionage and sabotage. Programmers can use lower-level functions but are encouraged to use crypto is expressed as a step-by-step procedure for Alice to encrypt and authenticate a packet; NaCl might compute

Bernstein, Daniel

264

Branching ratios for the beta decay of Na-21  

E-print Network

We have measured the beta-decay branching ratio for the transition from Na-21 to the first excited state of Ne-21. A recently published test of the standard model, which was based on a measurement of the beta-nu correlation in the decay of Na-21...

Iacob, V. E.; Hardy, John C.; Gagliardi, Carl A.; Goodwin, J.; Nica, N.; Park, H. I.; Tabacaru, G.; Trache, L.; Tribble, Robert E.; Zhai, Y.; Towner, I. S.

2006-01-01

265

Thyroid Na /I Symporter MECHANISM, STOICHIOMETRY, AND SPECIFICITY*  

E-print Network

Thyroid Na /I Symporter MECHANISM, STOICHIOMETRY, AND SPECIFICITY* (Received for publication, May College of Medicine, Bronx, New York 10461 The rat thyroid Na /I symporter (NIS) was expressed in Xenopus. It is now firmly established that active accumulation of io- dide (I ) by the thyroid gland epithelium

Eskandari, Sepehr

266

Adaptation of Tobacco Cells to NaCl 1  

PubMed Central

Cell lines of tobacco (Nicotiana tabacum L. var Wisconsin 38) were obtained which are adapted to grow in media with varying concentrations of NaCl, up to 35 grams per liter (599 millimolar). Salt-adapted cells exhibited enhanced abilities to gain both fresh and dry weight in the presence of NaCl compared to cells which were growing in medium without NaCl (unadapted cells). Tolerance of unadapted cells and cells adapted to 10 grams per liter NaCl was influenced by the stage of growth, with the highest degree of tolerance exhibited by cells in the exponential phase. Cell osmotic potential and turgor varied through the growth cycle of unadapted cells and cells at all levels of adaptation, with maximum turgor occurring at approximately the onset of exponential fresh weight accumulation. Adaptation to NaCl led to reduced cell expansion and fresh weight gain, while dry weight gain remained unaffected. This reduction in cell expansion was not due to failure of the cells to maintain turgor since cells adapted to NaCl underwent osmotic adjustment in excess of the change in water potential caused by the addition of NaCl to the medium. Tolerance of the adapted cells, as indicated by fresh or dry weight gain, did not increase proportionately with the increase in turgor. Adaptation of these glycophytic cells to NaCl appears to involve mechanisms which result in an altered relationship between turgor and cell expansion. Images Fig. 3 PMID:16664356

Binzel, Marla L.; Hasegawa, Paul M.; Handa, Avtar K.; Bressan, Ray A.

1985-01-01

267

Hydrothermal Synthesis of (K,Na)NbO3 Particles  

NASA Astrophysics Data System (ADS)

(K,Na)NbO3 (KNN) particles were successfully prepared by hydrothermal synthesis. The results showed that Na+ reacted more readily with Nb to form NaNbO3 than K+. For the purpose of obtaining KNN particles with K/Na=1, a mixed alkaline solution with K+/Na+ ratios ranging from 3.5/1 to 4/1 was required as a starting solution. The morphology and size of KNN particles synthesized strongly depended on K/Na ratio in the KNN particles. The KNN particles synthesized from the starting alkaline solution with K+/Na+=3.5/1 were the smallest with a pelletlike morphology affected by NaNbO3- and KNbO3-based particles. Surfactants such as sodium dodecylbenzenesulfonate (SDBS) and sodium hexametaphosphate (SH) were used to synthesize well dispersed and small KNN particles. Platelike KNN particles with 100 nm thickness and 1.5 µm width were obtained in this study.

Zhang, Fan; Han, Lu; Bai, Shan; Sun, Tiedong; Karaki, Tomoaki; Adachi, Masatoshi

2008-09-01

268

El Sexto Festival de Teatro Español del Siglo de Oro  

E-print Network

SPRING 1981 79 El Sexto Festival de Teatro Español del Siglo de Oro Arturo Pérez-Pisonero El Sexto Festival de Teatro Español del Siglo de Oro, celebrado en el Chamizal National Memorial en las fechas del 6 al 22 de marzo, ha presen tado, como... ofrece el teatro del Siglo de Oro. Y en tusiasmo, en este caso genuino, ha sido el del público, quien unas noches ha aplaudido los aciertos, y otras, como aquel otro de los corrales, se ha burlado jocosamente de la impericia de los actores. Pero al...

Pé rez-Pisonero, Arturo

1981-04-01

269

Dynamic polarizabilities and Van der Waals coefficients for alkali atoms Li, Na and alkali dimer molecules Li2, Na2 and NaLi  

NASA Astrophysics Data System (ADS)

The present paper gives an account of investigations of the polarizability of the alkali atoms Li, Na, diatomics homonuclear and heteronuclear Li2, Na2 and NaLi at SCF (Self Consistent Field) level of approximation and at correlated level, using a time Time-Dependent Gauge Invariant method (TDGI). Our static polarizability values agree with the best experimental and theoretical determinations. The Van der Waals C6 coefficients for the atom-atom, atom-dimer and dimer-dimer interactions have been evaluated. Les polarisabilités des atomes alcalins Li, Na, et des molécules diatomiques homonucléaires et hétéronucléaire Li2, Na2 et NaLi, ont été calculées au niveau SCF (Self Consistent Field) et au niveau corrélé à partir d'une méthode invariante de jauge dépendante du temps(TDGI). Nos valeurs des polarisabilités statiques sont en accord avec les meilleurs déterminations expérimentales et théoriques. Les coefficients C6 de Van de Waals pour les interactions atome-atome, atome-dimère et dimère-dimère ont également été évalués.

Mérawa, M.; Dargelos, A.

1998-07-01

270

The regio- and stereo-selective reduction of steroidal 4-en-3-ones using Na?S?O?/NaHCO? and CuCl/NaBH?.  

PubMed

This paper describes the regio- and stereoselective reduction of ??-3-keto moiety in certain steroids using Na?S?O?/NaHCO? and CuCl/NaBH?, respectively. Using either one of the two reduction agents in the reaction, the 17-substituents in the D ring were observed to have clearly influenced the stereoselective reduction of 4-ene in the A ring by the so-called conformational transmission effect. Na?S?O?/NaHCO? regioselectively reduced CC at 4-position of 17-substituted-androst-4-en-3-one derivatives to 5?-H-3-one as the main isomer. And as an extended application, Epiandrosterone (11) was further synthesized from androst-4-en-3,17-dione (AD) via four steps. The total yield from this was about 45%. In the presence of CuCl/NaBH?, ??-3-keto conjugated reduction of 17-spirocyclic ethylene ketal protected androst-4-en-3-one derivatives mainly produced 3?-hydroxy-5?-H isomers, at a yield around 81%. Considering the scaffold configuration of 3?-hydroxy-5?-H moiety coincided with that of bile acid analogs, this selective reduction could also be used as an alternative method for the synthetic study of bile acids using AD and its derivatives, which are from the microorganism degradation of natural sterols, as the potential materials. Meanwhile, configurations of the reductive compounds 5b, 6b, 9, 10 and 17e were identified by X-ray diffraction. PMID:24128809

Wang, Chunli; Chen, Xiaoyu; Huang, Yaoqing; Yang, Jesse; Chen, Ying

2013-12-20

271

[Catalytic properties of solubilized brain Na+,K+-ATPase].  

PubMed

The results are presented of a kinetic study of solubilized Na+, K+-ATPase obtained by 0.2+ digitonin from the NaI treated microsome fraction of the bull brain. It is shown that in main kinetic parameters (KmATP, V, pH-optimum, optimal [Na+]/[K+] ratio, etc.) the solubilized Na+, K+-ATPase does not differ essentially from membrane-bound enzyme. These results evidence for the absence of changes in principle for the kinetic behaviour of Na+,K+-ATPase when solubilized with digitonin. Simultaneously there are certain differences for a temperature dependence (the bend position in the Arrhenius anamorphosis) of the solubilized enzyme and its sensitivity to the action of strophanthin K. PMID:219575

Kravtsov, A V

1978-01-01

272

Dissociation of Methane Hydrate in Aqueous NaCl Solutions.  

PubMed

Molecular dynamics simulations of the dissociation of methane hydrate in aqueous NaCl solutions are performed. It is shown that the dissociation of the hydrate is accelerated by the formation of methane bubbles both in NaCl solutions and in pure water. We find two significant effects on the kinetics of the hydrate dissociation by NaCl. One is slowing down in an early stage before bubble formation, and another is swift bubble formation that enhances the dissociation. These effects arise from the low solubility of methane in NaCl solution, which gives rise to a nonuniform spatial distribution of solvated methane in the aqueous phase. We also demonstrate that bubbles form near the hydrate interface in dense NaCl solutions and that the hydrate dissociation proceeds inhomogeneously due to the bubbles. PMID:25237735

Yagasaki, Takuma; Matsumoto, Masakazu; Andoh, Yoshimichi; Okazaki, Susumu; Tanaka, Hideki

2014-10-01

273

The Na-K-ATPase and Calcium-Signaling Microdomains  

NSDL National Science Digital Library

The Na-K-ATPase is an energy-transducing ion pump that converts the free energy of ATP into transmembrane ion gradients. It also serves as a functional receptor for cardiotonic steroids such as ouabain and digoxin. Binding of ouabain to the Na-K-ATPase can activate calcium signaling in a cell-specific manner. The exquisite calcium modulation via the Na-K-ATPase is achieved by the ability of the pump to integrate signals from numerous protein and non-protein molecules, including ion transporters, channels, protein kinases/phosphatases, as well as cellular Na+. This review focuses on the unique properties of the Na-K-ATPase and its role in the formation of different calcium-signaling microdomains.

Jiang Tian (University of Toledo Health Science Campus Physiology and Pharmacology); Zi-jian Xie (University of Toledo Health Science Campus)

2008-08-01

274

NA60 results on thermal dimuons  

NASA Astrophysics Data System (ADS)

The NA60 experiment at the CERN SPS has measured muon pairs with unprecedented precision in 158 A GeV In-In collisions. A strong excess of pairs above the known sources is observed in the whole mass region 0.2< M<2.6 GeV. The mass spectrum for M<1 GeV is consistent with a dominant contribution from ? + ? -? ?? ? + ? - annihilation. The associated ? spectral function shows a strong broadening, but essentially no shift in mass. For M>1 GeV, the excess is found to be prompt, not due to enhanced charm production, with pronounced differences to Drell-Yan pairs. The slope parameter T eff associated with the transverse momentum spectra rises with mass up to the ?, followed by a sudden decline above. The rise for M<1 GeV is consistent with radial flow of a hadronic emission source. The seeming absence of significant flow for M>1 GeV and its relation to parton-hadron duality is discussed in detail, suggesting a dominantly partonic emission source in this region. A comparison of the data to the present status of theoretical modeling is also contained. The accumulated empirical evidence, including also a Planck-like shape of the mass spectra at low p T and the lack of polarization, is consistent with a global interpretation of the excess dimuons as thermal radiation. We conclude with first results on ? in-medium effects.

Arnaldi, R.; Banicz, K.; Borer, K.; Castor, J.; Chaurand, B.; Chen, W.; Cicalò, C.; Colla, A.; Cortese, P.; Damjanovic, S.; David, A.; de Falco, A.; Devaux, A.; Ducroux, L.; En'yo, H.; Fargeix, J.; Ferretti, A.; Floris, M.; Förster, A.; Force, P.; Guettet, N.; Guichard, A.; Gulkanian, H.; Heuser, J. M.; Keil, M.; Kluberg, L.; Li, Z.; Lourenço, C.; Lozano, J.; Manso, F.; Martins, P.; Masoni, A.; Neves, A.; Ohnishi, H.; Oppedisano, C.; Parracho, P.; Pillot, P.; Poghosyan, T.; Puddu, G.; Radermacher, E.; Ramalhete, P.; Rosinsky, P.; Scomparin, E.; Seixas, J.; Serci, S.; Shahoyan, R.; Sonderegger, P.; Specht, H. J.; Tieulent, R.; Usai, G.; Veenhof, R.; Wöhri, H. K.

2009-06-01

275

Ion exchange-induced dissolution of calcite in Na-montmorillonite/CaCO?b3?s systems: its effect on hydraulic conductivity, CaCO?b3?s dissolution kinetics, and CaCO?b3?s equilibrium relations  

E-print Network

Kinetics, and CaCOJ Equilibrium Relations. (December 1990) Jose Bruno Del Rio Durand, B. S. , Texas A/kM L'niversity Chair of Advisory Commiuee: Dr. Richard Loeppert The double decomposition reaction (DD) involves the dissolution of calcite... in the presence of an ion exchanger saturated or partially saturated with a cation other than Ca, usually Na. In this study, the potential effect of the double decomposition reamion on physical and chemical properties of soils was assessed in column studies...

Del Rio Durand, Jose Bruno

2012-06-07

276

Electrochemical Migration Characteristics of Eutectic Sn-Pb Solder Alloy in NaCl and Na2SO4 Solutions  

NASA Astrophysics Data System (ADS)

Anodic dissolution and the electrochemical migration characteristics of eutectic Sn-Pb solder alloy in deaerated 0.001% NaCl and Na2SO4 solutions were investigated using anodic polarization and water drop tests. Anodic polarization results revealed that a Pb-rich phase was preferentially ionized in deaerated 0.001% NaCl solution and an Sn-rich phase was predominantly ionized in deaerated 0.001% Na2SO4 solution, which coincides well with the composition of the dendrites formed during water drop tests. X-ray diffraction and photoelectron spectroscopy results showed that the surface oxide film formed on pure Sn in deaerated 0.001% NaCl solution is more stable than that formed on pure Sn in deaerated 0.001% Na2SO4 solution. The surface oxide film formed on pure Pb in deaerated 0.001% Na2SO4 solution is more stable than that formed on pure Sn in deaerated 0.001% NaCl solution. Therefore, the quality of the surface film of eutectic Sn-Pb solder in a chemical environment seems to be critical not only for corrosion resistance, but also for electrochemical migration resistance.

Jung, Ja-Young; Lee, Shin-Bok; Lee, Ho-Young; Joo, Young-Chang; Park, Young-Bae

2009-05-01

277

A semiclassical study of laser-induced atomic fluorescence from Na2, K2 and NaK  

NASA Technical Reports Server (NTRS)

A semiclassical treatment of laser-induced atomic fluorescence for the alkali-dimer systems Na2, K2 and NaK is presented. The variation of the fluorescence intensity with the frequency of the exciting laser photon is studied and a comparison of theoretical results with a set of experimental data is presented.

Yuan, J.-M.; Bhattacharyya, D. K.; George, T. F.

1982-01-01

278

Albedo polarimétrico de asteroides del grupo Hungaria  

NASA Astrophysics Data System (ADS)

La región del cinturón de asteroides en donde se encuentra el grupo de los Hungarias (a= 1.79 a 1.98 UA, i=15 a 40 grados) es la única zona donde es común encontrar objetos de tipo taxonómico E, caracterizados por altos albedos, colores relativamente neutros y espectros sin detalles. Este tipo de asteroides está relacionado espectralmente con ciertos meteoritos (aubritas) que indican la existencia de episodios de gran calentamiento que ocurrieron durante la formación del Sistema Solar. Como el espectro de los asteroides de tipo E es idéntico a los de tipo M y P, la única forma de clasificar un asteroide en alguno de estos tres tipos taxonómicos es mediante el albedo. En este trabajo se presentan resultados preliminares sobre la determinación polarimétrica de albedos para objetos de este grupo utilizando el polarímetro CASPROF de CASLEO.

Gil-Hutton, R.; Benavidez, P.

279

Una década de búsqueda del teatro hondureño  

E-print Network

colectiva, y por la efervescencia política de la época. De tres grupos se destacan: El Teatro Experimental la Merced (TEUM); El Teatro Obrero del Pueblo Unido (TOPU); y Teatro Popular Universitario (TPU). En estos grupos actúan jóvenes que despuntarán... de teatro popular e intento para generar una plataforma artística y de política cultural a tono con esa época de transformaciones sociales en Centroamérica. Su eslogan mismo, "Por SPRING 1992 109 un nuevo teatro para una nueva sociedad," fue punto...

Reyes G., Candelario

1992-04-01

280

ENERGIA DEL SOL Ts = 5780 K  

E-print Network

ENERGIA DEL SOL Ts = 5780 K P = 3, 86 � 1026 W Constant solar = 1377 W/m2 4H1 + 2e- He4 + 2 utilitzar per a aprofitar l'energia solar. #12;LA RADIACI´O SOLAR #12;LA RADIACI´O SOLAR #12;#12;#12;LA;APROFITAMENT DE LA RADIACI´O SOLAR La radiaci´o solar la podem convertir en altres formes d'energia per

Batiste, Oriol

281

Regulation of Cardiac Ca2+ Channel by Extracellular Na+  

PubMed Central

Hyponatremia is a predictor of poor cardiovascular outcomes during acute myocardial infarction and in the setting of preexisting heart failure [1]. There are no definitive mechanisms as to how hyponatremia suppresses cardiac function. In this report we provide evidence for direct down-regulation of Ca2+ channel current in response to low serum Na+. In voltage-clamped rat ventricular myocytes or HEK 293 cells expressing the L-type Ca2+ channel, a 15 mM drop in extracellular Na+ suppressed the Ca2+ current by ~15%; with maximal suppression of ~30% when Na+ levels were reduced to 100 mM or less. The suppressive effects of low Na+ on ICa, in part, depended on the substituting monovalent species (Li+, Cs+, TEA+), but were independent of phosphorylation state of the channel and possible influx of Ca2+ on Na+/Ca2+ exchanger. Acidification sensitized the Ca2+ channel current to Na+ withdrawal. Collectively our data suggest that Na+ and H+ may interact with regulatory site(s) at the outer recesses of the Ca2+ channel pore thereby directly modulating the electro-diffusion of the permeating divalents (Ca2+, Ba2+). PMID:21349579

Movafagh, Shahrzad; Cleemann, Lars; Morad, Martin

2011-01-01

282

Rigidification of the autolysis loop enhances Na+ binding to thrombin  

PubMed Central

Binding of Na+ to thrombin ensures high activity toward physiological substrates and optimizes the procoagulant and prothrombotic roles of the enzyme in vivo. Under physiological conditions of pH and temperature, the binding affinity of Na+ is weak due to large heat capacity and enthalpy changes associated with binding, and the Kd=80 mM ensures only 64% saturation of the site at the concentration of Na+ in the blood (140 mM). Residues controlling Na+ binding and activation have been identified. Yet, attempts to improve the interaction of Na+ with thrombin and possibly increase catalytic activity under physiological conditions have so far been unsuccessful. Here we report how replacement of the flexible autolysis loop of human thrombin with the homologous rigid domain of the murine enzyme results in a drastic (up to 10-fold) increase in Na+ affinity and a significant improvement in the catalytic activity of the enzyme. Rigidification of the autolysis loop abolishes the heat capacity change associated with Na+ binding observed in the wild-type and also increases the stability of thrombin. These findings have general relevance to protein engineering studies of clotting proteases and trypsin-like enzymes. PMID:21536369

Pozzi, Nicola; Chen, Raymond; Chen, Zhiwei; Bah, Alaji; Di Cera, Enrico

2011-01-01

283

Concentración del fragmento aminoterminal del pro-péptido natriurético cerebral en plasma como marcador biológico predictivo de mortalidad en las neumonías adquiridas en la comunidad.  

E-print Network

??Objetivo: Evaluar la relación entre la concentración plasmática del fragmento aminoterminal del pro-péptido natriurético cerebral (NT-proBNP) en el momento del diagnóstico de neumonía adquirida en… (more)

Tazón Varela, Manuel Antonio

2014-01-01

284

Two-frequency lidar technique for mesospheric Na temperature measurements  

NASA Technical Reports Server (NTRS)

This paper describes a new two-frequency lidar for measuring Na temperature profiles. The laser oscillator is tuned to the two operating frequencies by observing the Doppler-free structure of the Na D2 fluorescence spectrum in a vapor cell. The lidar technique and initial observations of the temperature profile between 82 and 102 km are described. Absolute temperature accuracies at the Na layer peak of better than + or - 3 K with a vertical resolution of 1 km and an integration period of approximately 5 min were achieved.

She, C. Y.; Latifi, H.; Yu, J. R.; Alvarez, R. J., II; Bills, R. E.

1990-01-01

285

Ion Program of Na61/Shine at the CERN SPS  

E-print Network

The NA61/SHINE experiment at the CERN SPS aims to discover the critical point of strongly interacting matter and study properties of the onset of deconfinement. These goals will be reached by measurements of hadron production properties in nucleus-nucleus, proton-proton and proton-lead interactions as a function of collision energy and size of the colliding nuclei. Furthermore, NA61/SHINE will perform numerous precision measurements needed for neutrino (T2K) and cosmic-ray (Pierre Auger Observatory and KASCADE) experiments. This paper summarizes physics arguments for the NA61/SHINE ion program and presents the status and plans of the experiment.

M. Gazdzicki; for the NA61/SHINE Collaboration

2008-12-23

286

Dianion formation from anion-alkali metal charge exchange reactions: TCNQ^- + Na -> TCNQ^-- + Na^+  

NASA Astrophysics Data System (ADS)

The interaction of an electron with an anion is characterized by a long-range coulomb repulsion and a short range polarizability attraction giving rise to a coulomb barrier. The permanent addition of an extra electron to a negatively charged anion requires tunneling through the barrier or attachment of the electron over the top of this coulomb barrier followed by disposal of the excess energy. Charge-exchange collisions of an anion with an alkali atom utilize the latter channel to produce permanent dianions with cross sections of ˜1 å^2. We have previously examined the reaction TCNQ-F4^- + Xe -> TCNQ-F4^-- + Xe^+ and reported a delayed threshold and quantum phase interference effects in the charge exchange cross section.ootnotetextS. Yu. Ovchinnikov, et al. Phys. Rev. A, 73, 64704(2006) Employing sodium as the collision partner, the cross section is seen to increase with decreasing energy with a threshold below 180 eV (com). A new apparatus has been constructed to allow measurements down to energies below the expected threshold (˜41 eV, laboratory energy based upon a 1 eV second electron affinity). This method has been used to study the reaction TCNQ^- + NA -> TCNQ^-- + Na^+ and will provide one of the first measurements of second electron affinities for molecular anions.

Smith, Byron; Compton, Robert; Ovchinnikov, Serge; Holm, Anne; Nielsen, Steen

2011-10-01

287

Phyla- and Subtype-Selectivity of CgNa, a Na+ Channel Toxin from the Venom of the Giant Caribbean Sea Anemone Condylactis Gigantea  

PubMed Central

Because of their prominent role in electro-excitability, voltage-gated sodium (NaV) channels have become the foremost important target of animal toxins. These toxins have developed the ability to discriminate between closely related NaV subtypes, making them powerful tools to study NaV channel function and structure. CgNa is a 47-amino acid residue type I toxin isolated from the venom of the Giant Caribbean Sea Anemone Condylactis gigantea. Previous studies showed that this toxin slows the fast inactivation of tetrodotoxin-sensitive NaV currents in rat dorsal root ganglion neurons. To illuminate the underlying NaV subtype-selectivity pattern, we have assayed the effects of CgNa on a broad range of mammalian isoforms (NaV1.2–NaV1.8) expressed in Xenopus oocytes. This study demonstrates that CgNa selectively slows the fast inactivation of rNaV1.3/?1, mNaV1.6/?1 and, to a lesser extent, hNaV1.5/?1, while the other mammalian isoforms remain unaffected. Importantly, CgNa was also examined on the insect sodium channel DmNaV1/tipE, revealing a clear phyla-selectivity in the efficacious actions of the toxin. CgNa strongly inhibits the inactivation of the insect NaV channel, resulting in a dramatic increase in peak current amplitude and complete removal of fast and steady-state inactivation. Together with the previously determined solution structure, the subtype-selective effects revealed in this study make of CgNa an interesting pharmacological probe to investigate the functional role of specific NaV channel subtypes. Moreover, further structural studies could provide important information on the molecular mechanism of NaV channel inactivation. PMID:21833172

Billen, Bert; Debaveye, Sarah; Beress, Laszlo; Tytgat, Jan

2010-01-01

288

Characterization of Na-X, NaA, and coal fly ash zeolites and their amorphous precursors by IR, MAS NMR and XPS  

Microsoft Academic Search

By fusion with sodium hydroxide followed by a hydrothermal reaction, fly ash and Alenriched fly ash were converted into Na-X and Na-A zeolites, respectively. The authentic Na-X, Na-A and fly ash zeolites as well as their amorphous precursors have been characterized by IR, 29Si and 27Al MAS NMR, XPS\\/AES, TG, and comparative ion-exchange studies of Cs and K with Na

N. Shigemoto; S. Sugiyama; H. Hayashi; K. Miyaura

1995-01-01

289

Determinants of substrate and cation transport in the human Na+/dicarboxylate cotransporter NaDC3.  

PubMed

Metabolic intermediates, such as succinate and citrate, regulate important processes ranging from energy metabolism to fatty acid synthesis. Cytosolic concentrations of these metabolites are controlled, in part, by members of the SLC13 gene family. The molecular mechanism underlying Na(+)-coupled di- and tricarboxylate transport by this family is understood poorly. The human Na(+)/dicarboxylate cotransporter NaDC3 (SLC13A3) is found in various tissues, including the kidney, liver, and brain. In addition to citric acid cycle intermediates such as ?-ketoglutarate and succinate, NaDC3 transports other compounds into cells, including N-acetyl aspartate, mercaptosuccinate, and glutathione, in keeping with its dual roles in cell nutrition and detoxification. In this study, we construct a homology structural model of NaDC3 on the basis of the structure of the Vibrio cholerae homolog vcINDY. Our computations are followed by experimental testing of the predicted NaDC3 structure and mode of interaction with various substrates. The results of this study show that the substrate and cation binding domains of NaDC3 are composed of residues in the opposing hairpin loops and unwound portions of adjacent helices. Furthermore, these results provide a possible explanation for the differential substrate specificity among dicarboxylate transporters that underpin their diverse biological roles in metabolism and detoxification. The structural model of NaDC3 provides a framework for understanding substrate selectivity and the Na(+)-coupled anion transport mechanism by the human SLC13 family and other key solute carrier transporters. PMID:24808185

Schlessinger, Avner; Sun, Nina N; Colas, Claire; Pajor, Ana M

2014-06-13

290

Calculation of spectroscopic constants and radiative parameters for the B 1?- X 1?+ electronic transitions of NaK, NaRb, and NaCs molecules  

NASA Astrophysics Data System (ADS)

The vibrational, rotational, and centrifugal spectroscopic constants and the radiative parameters (the Einstein coefficients, oscillator strengths, Frank-Condon factors, r v'v? centroids, and wavenumbers of rotational lines) of electronic-vibrational-rotational transitions in the systems of bands B 1? - X 1?+ of NaK (0 ? v' ? 14, 0 ? v? ? 52, j = 0, 30, 50, 70, 80, and 100), NaRb (0 ? v' ? 12, 0 ? v? ? 51, j = 0, 20, 30, 50, 70, 90, 100, and 120), and NaCs (0 ? v' ? 10, 0 ? v? ? 44, j = 0, 30, 50, 70, 90, 100, and 120) molecules, as well as the radiative lifetimes of excited electronic states, are calculated. Calculations are performed based on semiempirical potential curves constructed in this work. The calculated spectroscopic constants and the radiative lifetimes are compared with experimental values.

Smirnov, A. D.

2014-09-01

291

Na double-edge magneto-optic filter for Na lidar profiling of wind and temperature in the lower atmosphere.  

PubMed

A Na double-edge magneto-optic filter is proposed for incorporation into the receiver of a three-frequency Na Doppler lidar to extend its wind and temperature measurements into the lower atmosphere. Two prototypes based on cold- and hot-cell designs were constructed and tested with laser scanning and quantum mechanics modeling. The hot-cell filter exhibits superior performances over the cold-cell filter containing buffer gas. Lidar simulations, metrics, and error analyses show that simultaneous wind and temperature measurements are feasible in the altitude range of 20-50 km using the hot-cell filter and reasonable Na lidar parameters. PMID:19148254

Huang, Wentao; Chu, Xinzhao; Williams, B P; Harrell, S D; Wiig, Johannes; She, C-Y

2009-01-15

292

O, Na, Ba and Eu abundance patterns in open clusters  

E-print Network

Open clusters are historically regarded as single-aged stellar populations representative of star formation within the Galactic disk. Recent literature has questioned this view, based on discrepant Na abundances relative to the field, and concerns about the longevity of bound clusters contributing to a selection bias: perhaps long-lived open clusters are chemically different to the star formation events that contributed to the Galactic disk. We explore a large sample of high resolution Na, O, Ba & Eu abundances from the literature, homogenized as much as reasonable including accounting for NLTE effects, variations in analysis and choice of spectral lines. Compared to a template globular cluster and representative field stars, we find no significant abundance trends, confirming that the process producing the Na-O anti-correlation in globular clusters is not present in open clusters. Furthermore, previously reported Na-enhancement of open clusters is found to be an artefact of NLTE effects, with the open cl...

MacLean, B T; Lattanzio, J

2014-01-01

293

Na+-K+ Pump Regulation and Skeletal Muscle Contractility  

NSDL National Science Digital Library

The present review is written with the specific purpose of analyzing how regulation of the activity and the capacity of the Na+-K+ pumps influences excitability and contractile performance in skeletal muscle.

MD Torben Clausen (University of Aarhus Department of Physiology)

2003-10-01

294

Na decorated B6 cluster and its hydrogen storage properties  

NASA Astrophysics Data System (ADS)

The structures and hydrogen storage properties of sodium atoms decorated B6 clusters are investigated by the B3LYP method with a 6-311+G (d, p) basis set. For NamB6 (m = 1-3) clusters, Na atoms are always inclined to separate far enough from each other and not cluster together on a B6 cluster surface so that each Na atom has sufficient space to bind hydrogen molecules. The hydrogen storage gravimetric density of a two Na atoms decorated B6 cluster is 17.91 wt% with an adsorption energy per H2 molecule (AAE/H2) of 0.6851 kcal·mol-1. The appropriate AAE/H2 and preferable gravimetric density of the two Na atoms decorated B6 cluster complex indicate that it is feasible for hydrogen storage application in ambient conditions.

Ruan, Wen; Wu, Dong-Lan; Luo, Wen-Lang; Yu, Xiao-Guang; Xie, An-Dong

2014-02-01

295

Regulation of Na v channels in sensory neurons.  

PubMed

Voltage-gated Na(+) channels have an essential role in the biophysical properties of nociceptive neurons. Factors that regulate Na(+) channel function are of interest from both pathophysiological and therapeutic perspectives. Increasing evidence indicates that changes in expression or inappropriate modulation of these channels leads to electrical instability of the cell membrane and the inappropriate spontaneous activity that is observed following nerve injury, and that this might contribute to neuropathic pain. The role of Na(v) channels in nociception depends on modulation by factors such as auxiliary beta-subunits, cytoskeletal proteins and the phosphorylation state of neurons. In this review we describe the modulation of Na(v) channels on sensory neurons by auxiliary beta-subunits, protein kinases and cytoskeletal proteins. PMID:16125256

Chahine, Mohamed; Ziane, Rahima; Vijayaragavan, Kausalia; Okamura, Yasushi

2005-10-01

296

Silver, zinc, and copper exchange in a Na-clinoptilolite and resulting effect on antibacterial activity  

Microsoft Academic Search

Ag+–Na+, Zn2+–Na+, and Cu2+–Na+ equilibria for clinoptilolite-rich mineral from Gördes (Western Anatolia) were investigated at 25 °C and 0.1 N total solution normality. While silver exchange was favorable over the whole concentration range, zinc and copper were partially exchanged and preferred only at low concentrations. The standard free energies of exchanges for Ag+–Na+, Zn2+–Na+, and Cu2+–Na+ pairs were found as

Ayben Top; Semra Ülkü

2004-01-01

297

Calpain inhibition promotes the rescue of F(508)del-CFTR in PBMC from cystic fibrosis patients.  

PubMed

A basal calpain activity promotes the limited proteolysis of wild type (WT) cystic fibrosis conductance regulator (CFTR), inducing the internalization of the split channel. This process contributes to the regulation in the level of the active CFTR at the plasma membranes. In peripheral blood mononuclear cells (PBMC) from 16 healthy donors, the inhibition of calpain activity induces a 3-fold increase in the amount of active WT CFTR at the plasma membranes. Instead, in PBMC from cystic fibrosis (CF) patients, calpain activity is expressed at aberrant levels causing the massive removal of F(508)del-CFTR from the cell surface. In these patients, the inhibition of such abnormal proteolysis rescues physiological amounts of active mutated CFTR in 90% of the patients (25 over 28). The recovery of functional F(508)del-CFTR at the physiological location, in cells treated with a synthetic calpain inhibitor, indicates that F(508)del-CFTR folding, maturation, and trafficking operate in CF-PBMC at significant rate. Thus, an increase in the basal calpain activity seems primarily involved in the CFTR defect observed in various CF cells. Furthermore, in CF-PBMC the recovery of the scaffolding protein Na(+)/H(+) exchanger regulatory factor 1 (NHERF-1), occurring following inhibition of the aberrant calpain activity, can contribute to rescue CFTR-functional clusters. PMID:23785472

Averna, Monica; Pedrazzi, Marco; Minicucci, Laura; De Tullio, Roberta; Cresta, Federico; Salamino, Franca; Pontremoli, Sandro; Melloni, Edon

2013-01-01

298

1674 -XIV Encuentro de Latinoamericanistas Espaoles DITADURA MILITAR NA  

E-print Network

1674 - XIV Encuentro de Latinoamericanistas Españoles DITADURA MILITAR NA AM�RICA LATINA E O, significativas decisões sobre o legado autoritário das ditaduras militares na América Latina das décadas de 1970 transição. No entanto, no Brasil, não só não houve responsabilização pelos crimes da ditadura, como há uma

Paris-Sud XI, Université de

299

Measurement of Na +,K +ATPase Activity in Human Skeletal Muscle  

Microsoft Academic Search

There are few published measures of Na+,K+-ATPase activity in human skeletal muscle. This study investigated the suitability of the K+-stimulated 3-O-methylfluorescein phosphatase assay for measurement of Na+,K+-ATPase activity in human skeletal muscle. Factors investigated include enzyme kinetics, sample treatment, and ligand concentration. The addition of ouabain blocked maximal K+-stimulated 3-O-methylfluorescein phosphatase (3-O-MFPase) activity, confirming the specificity of the assay. Activity

Steve F. Fraser; Michael J. McKenna

1998-01-01

300

Vanadate stimulates the pumped movements of Na in skeletal muscle  

Microsoft Academic Search

We have measured the effects of concentrations of vanadate ranging between 0.01 and 10 mM on the22Na efflux of frog sartorius muscles. The addition of vanadate had no effects when concentrations lower than 0.5 mM were used; higher concentrations increased Na efflux. The increase was abolished by the addition of ouabain (10-5M). In muscles pretreated with ouabain vanadate did not

David Erlij

1984-01-01

301

In vivo modification of Na +,K +ATPase activity in Drosophila  

Microsoft Academic Search

We have constructed and characterized transgenic Drosophila lines with modified Na+,K+-ATPase activity. Using a temperature dependent promoter from the hsp70 gene to drive expression of wild-type ? subunit cDNA, we can conditionally rescue bang-sensitive paralysis and ouabain sensitivity of a Drosophila Na+,K+-ATPase ? subunit hypomorphic mutant, 2206. In contrast, a mutant ? subunit (?D369N) leads to increased bang-sensitive paralysis and

Banghua Sun; Peizhang Xu; Weiya Wang; Paul M. Salvaterra

2001-01-01

302

g State of Na2: Vibrational Numbering and Hyperfine Structure  

E-print Network

The 43 g State of Na2: Vibrational Numbering and Hyperfine Structure G. Lazarov,* A. M. Lyyra,*,1 The Na2 43 g state has been studied by continuous-wave (cw) perturbation-facilitated optical of the 43 g (v, N) 4 b3 u (vb, J ) A1 u (vA, J ) 4 X1 g (v , J ) transitions show hyperfine splittings

Huennekens, John

303

Metal Fluoride Complexes of Na,K-ATPase  

PubMed Central

The Na,K-ATPase belongs to the P-type ATPase family of primary active cation pumps. Metal fluorides like magnesium-, beryllium-, and aluminum fluoride act as phosphate analogues and inhibit P-type ATPases by interacting with the phosphorylation site, stabilizing conformations that are analogous to specific phosphoenzyme intermediates. Cardiotonic steroids like ouabain used in the treatment of congestive heart failure and arrhythmias specifically inhibit the Na,K-ATPase, and the detailed structure of the highly conserved binding site has recently been described by the crystal structure of the shark Na,K-ATPase in a state analogous to E2·2K+·Pi with ouabain bound with apparently low affinity (1). In the present work inhibition, and subsequent reactivation by high Na+, after treatment of shark Na,K-ATPase with various metal fluorides are characterized. Half-maximal inhibition of Na,K-ATPase activity by metal fluorides is in the micromolar range. The binding of cardiotonic steroids to the metal fluoride-stabilized enzyme forms was investigated using the fluorescent ouabain derivative 9-anthroyl ouabain and compared with binding to phosphorylated enzyme. The fastest binding was to the Be-fluoride stabilized enzyme suggesting a preformed ouabain binding cavity, in accord with results for Ca-ATPase where Be-fluoride stabilizes the E2-P ground state with an open luminal ion access pathway, which in Na,K-ATPase could be a passage for ouabain. The Be-fluoride stabilized enzyme conformation closely resembles the E2-P ground state according to proteinase K cleavage. Ouabain, but not its aglycone ouabagenin, prevented reactivation of this metal fluoride form by high Na+ demonstrating the pivotal role of the sugar moiety in closing the extracellular cation pathway. PMID:21708939

Cornelius, Flemming; Mahmmoud, Yasser A.; Toyoshima, Chikashi

2011-01-01

304

Stabilization of Na,K–ATPase by ionic interactions  

Microsoft Academic Search

The effect of ions on the thermostability and unfolding of Na,K–ATPase from shark salt gland was studied and compared with that of Na,K–ATPase from pig kidney by using differential scanning calorimetry (DSC) and activity assays. In 1 mM histidine at pH 7, the shark enzyme inactivates rapidly at 20 °C, as does the kidney enzyme at 42 °C (but not at 20 °C). Increasing

Elfrieda Fodor; Natalya U. Fedosova; Csilla Ferencz; Derek Marsh; Tibor Pali; Mikael Esmann

2008-01-01

305

An empirical NaKCa geothermometer for natural waters  

USGS Publications Warehouse

An empirical method of estimating the last temperature of water-rock interaction has been devised. It is based upon molar Na, K and Ca concentrations in natural waters from temperature environments ranging from 4 to 340??C. The data for most geothermal waters cluster near a straight line when plotted as the function log ( Na K) + ?? log [ ??? (Ca) Na] vs reciprocal of absolute temperature, where ?? is either 1 3 or 4 3 depending upon whether the water equilibrated above or below 100??C. For most waters tested, the method gives better results than the Na K methods suggested by other workers. The ratio Na K should not be used to estimate temperature if ??? ( MCa) MNa is greater than 1. The Na K values of such waters generally yield calculated temperatures much higher than the actual temperature at which water interacted with the rock. A comparison of the composition of boiling hot-spring water with that obtained from a nearby well (170??C) in Yellowstone Park shows that continued water-rock reactions may occur during ascent of water even though that ascent is so rapid that little or no heat is lost to the country rock, i.e. the water cools adiabatically. As a result of such continued reaction, waters which dissolve additional Ca as they ascend from the aquifer to the surface will yield estimated aquifer temperatures that are too low. On the other hand, waters initially having enough Ca to deposit calcium carbonate during ascent may yield estimated aquifer temperatures that are too high if aqueous Na and K are prevented from further reaction with country rock owing to armoring by calcite or silica minerals. The Na-K-Ca geothermometer is of particular interest to those prospecting for geothermal energy. The method also may be of use in interpreting compositions of fluid inclusions. ?? 1973.

Fournier, R.O.; Truesdell, A.H.

1973-01-01

306

The thermopower of liquid Na-Sn alloys  

Microsoft Academic Search

The thermopower, Q, of liquid Na-Sn alloys has been measured as a function of temperature and composition. This alloys system shows a non-NFE behaviour in large parts of the composition range. For dilute Na-Sn alloys, it is shown that the measurements are consistent with a very simple phase-shift calculation. For concentrated alloys, a theoretical interpretation is complicated by the existence

J. A. Meijer; W. van der Lugt

1991-01-01

307

Effect of dronedarone on Na + , Ca 2+ and HCN channels  

Microsoft Academic Search

Previous studies showed that amiodarone causes state-dependent inhibition of Na+ channels thereby mediating an atrial-selective drug effect. The aim of the present study was to investigate the impact of\\u000a the new antiarrhythmic compound dronedarone on Na+, Ca2+ and hyperpolarization-activated cyclic nucleotide-gated ion channels. Monophasic action potentials (MAP) and effective refractory\\u000a period (ERP) were studied in arterially perfused left atria and

Roman Bogdan; Heinz Goegelein; Hartmut Ruetten

2011-01-01

308

A stable Na + \\/H + antiporter of thermophilic bacterium PS3  

Microsoft Academic Search

As a first step in the isolation of a stable Na+\\/H+ antiporter, its reaction in sonicated membrane vesicles of thermophilic bacterium PS3 has been characterized. The sonicated vesicles showed quenching of quinacrine fluorescence in either NADH oxidation or ATP hydrolysis. The quenching was reversed by the addition of Na+, Li+, Mn2+, Cd2+, and Co2+, but not of choline+ or Ca2+,

Kimihiko Goto I; Hajime Hirata; Yasuo Kagawa

1980-01-01

309

DERECHOS DEL EMPLEADO LEy PARA LA PROtECCin  

E-print Network

DERECHOS DEL EMPLEADO LEy PARA LA PROtECCión DEL EMPLEADO COntRA LA PRuEbA DEL POLígRAfO PROHIBICIONES ExENCIONES DERECHOS DE LOS ExAMINADOS CUMPLIMIENTO Generalmente se le prohíbe al empleador que le aspirante a un trabajo por haberse negado a someterse a la prueba o por haberse acogido a otros derechos

Rock, Chris

310

julio-septiembre2006Cinvestav74 Resea del libro  

E-print Network

julio-septiembre2006·Cinvestav74 Reseña del libro Ejemplos prácticos del uso de la resonancia Departamento de Química en 1993, conocería personalmente a todos los autores del libro. En algunas ocasiones comenté con ellos la dificultad de encontrar libros de texto en los que se abordaran ejemplos reales

311

An evening at "La Clinica del Pueblo".  

PubMed

This article describes a typical evening at the Clinica del Pueblo in the Hispanic neighborhood of Adams-Morgan in Washington, D.c. The Clinical del Pueblo began operating in 1983 in response to the urgen medical needs of Central American refugees arriving in the Washington D.c. area. The refugees bring with them severe trauma, fear, and health problems caused by the civil was and exacerbated by inadequate or non-existant health services. Approximately 80,000 Salvadoran refugees live in the area. They do not receive adequate health care for 3 reasons. 1) Because the US goverment is unwilling to recognize them as true refugees, they live with the constant threat of deportatin back to the violence from which they have fled. 2) Refugees lack the ability to pay for private care. 3) Langauage and culture create frightening barriers to health care for the refugees. For those who do seek care, these barriers can lead to the inadequate or incomplete diagnoses and poor compliance and follow-up. Plenty International and the Central American Refugee Center responded to these problems by organizing a free clinic to provide not only medical care but also a training course for volunteers. The director of the clinic organizes the course, the classes are taught by a variety of people including the clinic's volunteer physicians, nurses, and public health educators as well as graduates of previus training courses and people from the wider community. The services of the clinic reach only a small portion of the population in need. However, the fact that free medical services are now available to some Central American refugees make the Clinica del Pueblo an important program. PMID:12281149

Shefsky, M L

1986-01-01

312

Reactions of NaCl with Gaseous SO3, SO2, and O2  

NASA Technical Reports Server (NTRS)

Hot corrosion of gas turbine engine components involves deposits of Na2SO4 which are produced by reactions between NaCl and oxides of sulfur. For the present investigation, NaCl single crystals were exposed at 100 to 850 C to gaseous mixtures of SO3, SO2, and O2. The products formed during this exposure depend, primarily, on the temperatures. The four product films were: NaCl-SO3; Na2S2O7; Na2SO4; and NaCl-Na2SO4. The kinetics of the reactions were measured.

Fielder, W. L.; Stearns, C. A.; Kohl, F. J.

1983-01-01

313

Na-caseinate/oil/water systems: emulsion morphology diagrams.  

PubMed

The concentrated (dispersed phase 50-70 wt%) composition space of Na-caseinate, a family of milk proteins, stabilised emulsions was investigated for three different oils: soybean oil, palm olein and tetradecane with pH 6.8 phosphate buffer continuous phase. The variation of emulsion stability and microstructure were explored using static light scattering, diffusion nuclear magnetic resonance, cryo-scanning electron microscopy, rheology and the time varying macroscopic phase separation of the emulsions. For soybean oil and palm olein a rich diversity of emulsion microstructures and stabilities are realised. Five emulsion domains, each having a different microstructure and macroscopic stability have been identified within the composition space probed. For the lowest concentrations of emulsifier bridging flocculation is evident and emulsions are of low stability. Increasing Na-caseinate concentration leads to an increased stability and the existence of distinct individual oil droplets, visualised using cryo-scanning electron microscopy. Further increases in Na-caseinate concentration reduce emulsion stability due to depletion flocculation. Na-caseinate self-assembly is then initiated. At sufficiently high Na-caseinate and/or oil concentrations the continuous phase of the emulsion is a three-dimensional protein network and emulsion stability is again enhanced. At the limits of the emulsion composition space a gel-like paste is formed. The diversity of emulsion microstructure is reduced when tetradecane is the discrete phase. Na-caseinate self-assembly is limited and there is no evidence for formation of a protein network. PMID:22709624

Tan, Hui Lin; McGrath, Kathryn M

2012-09-01

314

Band gap engineering for graphene by using Na+ ions  

NASA Astrophysics Data System (ADS)

Despite the noble electronic properties of graphene, its industrial application has been hindered mainly by the absence of a stable means of producing a band gap at the Dirac point (DP). We report a new route to open a band gap (Eg) at DP in a controlled way by depositing positively charged Na+ ions on single layer graphene formed on 6H-SiC(0001) surface. The doping of low energy Na+ ions is found to deplete the ?* band of graphene above the DP, and simultaneously shift the DP downward away from Fermi energy indicating the opening of Eg. The band gap increases with increasing Na+ coverage with a maximum E g ? 0.70 eV. Our core-level data, C 1s, Na 2p, and Si 2p, consistently suggest that Na+ ions do not intercalate through graphene, but produce a significant charge asymmetry among the carbon atoms of graphene to cause the opening of a band gap. We thus provide a reliable way of producing and tuning the band gap of graphene by using Na+ ions, which may play a vital role in utilizing graphene in future nano-electronic devices.

Sung, S. J.; Lee, P. R.; Kim, J. G.; Ryu, M. T.; Park, H. M.; Chung, J. W.

2014-08-01

315

MoNA and initial measurements with 7He Resonance *  

NASA Astrophysics Data System (ADS)

Of recent interest in the study of exotic nuclei are neutron rich nuclei near and beyond the drip line. Using radioactive beams produced at the National Superconducting Cyclotron Laboratory (NSCL), the Modular Neutron Array (MoNA) detector, and a 4 Tesla sweeper magnet it is possible to study these nuclei. MoNA is a large area, high-efficiency neutron detector consisting of 144 plastic scintillating bars. When used in tandem with the series of detectors and scintillators in the sweeper setup MoNA is capable of detecting neutrons in coincidence with reaction fragments detected at the sweeper. As an initial experiment to test the tandem setup of MoNA and the sweeper a secondary beam of 8Li was produced in the coupled cyclotron facility and the reaction of interest, stripping off a proton to observe the resonance of 7He immediately decaying to 6He+n, was studied with MoNA and the sweeper. The ground state of 7He resonance was observed in the relative velocities of 6He and the neutron. *MoNA collaboration is supported by the NSF. TP, RP acknowledge the support from the NSF Research Experience for Undergraduates program.

Pike, Tina; Pepin, Robert

2004-10-01

316

Clusters of axonal Na+ channels adjacent to remyelinating Schwann cells.  

PubMed

Rat sciatic nerve fibres were demyelinated by injection of lysolecithin and examined at several stages as Schwann cells proliferated, adhered, and initiated remyelination. Immunoperoxidase EM has been used to follow the clustering of Na+ channels that represents an early step in the formation of new nodes of Ranvier. At the peak of demyelination, 1 week post-injection, only isolated sites, suggestive of the original nodes, were labelled. As Schwann cells adhered and extended processes along the axons, regions of axonal Na+ channel immunoreactivity were often found just beyond their leading edges. These channel aggregates were associated only with the axolemma and Na+ channels were not detected on glial membranes. Sites with more than one cluster in close proximity and broadly labelled aggregates between Schwann cells suggested that new nodes of Ranvier formed as neighbouring Na+ channel groups merged. Schwann cells thus seem to play a major role in ion channel distributions in the axolemma. In all of these stages Na+ channel label was found primarily just outside the region of close contact between axon and Schwann cell. This suggests that Schwann cell adherence acts in part to exclude Na+ channels, or that diffusible substances are involved and can act some distance from regions of direct contact. PMID:8835788

Novakovic, S D; Deerinck, T J; Levinson, S R; Shrager, P; Ellisman, M H

1996-06-01

317

RELACIÓN MÉDICO PACIENTE: DERECHOS DEL ADULTO MAYOR  

PubMed Central

Existen prejuicios en relación con la vejez, incluso entre los profesionales que se dedican a la gerontología. Uno común y peligroso es considerar que los viejos son todos enfermos o discapacitados. La relación médico-paciente es la piedra angular de la práctica y ética médicas. Para alcanzar el respeto por los adultos mayores es necesaria una medicina prudente, basada en una práctica en la cual la reflexión ética y clínica pueda contribuir. Esto último es posible si se hacen valer los derechos del adulto mayor, en particular como paciente para la toma de decisiones. PMID:20379380

Barrantes-Monge, Melba; Rodríguez, Eduardo; Lama, Alexis

2009-01-01

318

Boletín del Instituto Nacional del Cáncer - 11 de septiembre de 2012  

Cancer.gov

Con la ayuda de herramientas genéticas, investigadores han identificado subconjuntos de células que parecen impulsar el crecimiento de tumores en ratones. Estos resultados ofrecen factores adicionales que sustentan la hipótesis de la existencia de células madre del cáncer, es decir, la idea de que algunos tumores contienen células que se autorenuevan y dan origen a todo tipo de células tumorales.

319

Análisis del dispositivo de balón coil para la oclusión del Ductus Arterioso Persistente  

Microsoft Academic Search

RESUMEN: El ductus arterioso persistente (PDA) es uno de los defectos cardiacos congénitos más comunes. Consiste en una comunicación vascular anormal durante la vida extrauterina, entre la aorta descendente y la arteria pulmonar izquierda. El PDA puede llevar al desarrollo de complicaciones importantes como hipertensión pulmonar, edema pulmonar y endocarditis bacteriana. Actualmente el manejo del PDA se hace por medio

A. C. Silva; J. C. Briceño; A. García

320

V Festival Nacional del Nuevo Teatro: Las fuentes inagotables del arte  

E-print Network

intento por recrear teatralmente las peripecias del narco-tráfico en Colombia con Golpe de suerte, es indudable que el conjunto dramático La Candelaria ha aprendido de sus fracasos para sorprendernos con el montaje de una obra que, en consenso de los...

Má rceles Daconte, Eduardo

1982-10-01

321

Efecto del Programa de Entrenamiento “Manejo del Dolor” en la Documentación de Enfermería en el Expediente Electrónico  

PubMed Central

Resumen En el presente trabajo se muestra la importancia de entrenar al personal de enfermería para mejorar la documentación en el expediente electrónico. Se eligió el manejo del dolor por ser un área prioritaria; una alta proporción de pacientes en período post operatorio cursa con dolor, por lo tanto, la documentación debe ser útil para la toma de decisiones clínicas. Se implementó un programa de entrenamiento denominado “Manejo del Dolor” dirigido al personal de enfermería. Se utilizó la tecnología de la información como herramienta para fortalecer el conocimiento con base en la revisión sistemática de la literatura; el personal de enfermería participante seleccionó la mejor evidencia; posteriormente se trabajó en la transferencia de este conocimiento a la práctica a través del diseño de un protocolo para el manejo del dolor. Se concluye que el conocimiento del manejo del dolor es fundamental para que enfermería documente con mayor precisión sus intervenciones. PMID:24199106

Monsiváis, María Guadalupe Moreno; Guzmán, Ma. Guadalupe Interial; Flores, Paz Francisco Sauceda; Arreola, Leticia Vázquez

2012-01-01

322

Study on the transformation from NaCl-type Na2TiO3 to layered titanate  

NASA Astrophysics Data System (ADS)

NaCl-type crystal structure sodium titanate (Na2TiO3), which exhibits a unit cell parameter of a=4.49 Å, was obtained by high temperature molten salt reaction. An intermediate phase product with layered structure was prepared by leaching the obtained Na2TiO3. We propose that the layered titanate structure is composed of Na2TiO3 and H2O, corresponding to the host-layer and guest-substance, respectively. Furthermore, the crystal structures of layered titanate were optimized by the density functional theory (DFT). This indicates that water molecules are distributed in an orderly manner in the interlayer through the formation of hydrogen-bonded chain. Moreover, the position of the adjacent lamella translates to c/2 along the c-axis after the intercalation of water.

Liu, Y. H.; Zhao, W.; Wang, W. J.; Yang, X.; Chu, J. L.; Xue, T. Y.; Qi, T.; Wu, J. Y.; Wang, C. R.

2012-03-01

323

Copper toxicity in cultured human skeletal muscle cells: the involvement of Na + \\/K + ATPase and the Na + \\/Ca 2+ -exchanger  

Microsoft Academic Search

Copper (Cu2+) intoxication has been shown to induce pathological changes in various tissues. The mechanism underlying Cu2+ toxicity is still unclear. It has been suggested that the Na+\\/K+-ATPase and\\/or a change of the membrane permeability may be involved. In this study we examined the effects of Cu2+ on the Na+ and Ca2+ homeostasis of cultured human skeletal muscle cells using

Ad A. G. M. Benders; Jie Li; Robert A. C. Lock; René J. M. Bindels; Sjoerd E. Wendelaar Bonga; Jacques H. Veerkamp

1994-01-01

324

Na(+) transport, and the E(1)P-E(2)P conformational transition of the Na(+)/K(+)-ATPase.  

PubMed Central

We have used admittance analysis together with the black lipid membrane technique to analyze electrogenic reactions within the Na(+) branch of the reaction cycle of the Na(+)/K(+)-ATPase. ATP release by flash photolysis of caged ATP induced changes in the admittance of the compound membrane system that are associated with partial reactions of the Na(+)/K(+)-ATPase. Frequency spectra and the Na(+) dependence of the capacitive signal are consistent with an electrogenic or electroneutral E(1)P <--> E(2)P conformational transition which is rate limiting for a faster electrogenic Na(+) dissociation reaction. We determine the relaxation rate of the rate-limiting reaction and the equilibrium constants for both reactions at pH 6.2-8.5. The relaxation rate has a maximum value at pH 7.4 (approximately 320 s(-1)), which drops to acidic (approximately 190 s(-1)) and basic (approximately 110 s(-1)) pH. The E(1)P <--> E(2)P equilibrium is approximately at a midpoint position at pH 6.2 (equilibrium constant approximately 0.8) but moves more to the E(1)P side at basic pH 8.5 (equilibrium constant approximately 0.4). The Na(+) affinity at the extracellular binding site decreases from approximately 900 mM at pH 6.2 to approximately 200 mM at pH 8.5. The results suggest that during Na(+) transport the free energy supplied by the hydrolysis of ATP is mainly used for the generation of a low-affinity extracellular Na(+) discharge site. Ionic strength and lyotropic anions both decrease the relaxation rate. However, while ionic strength does not change the position of the conformational equilibrium E(1)P <--> E(2)P, lyotropic anions shift it to E(1)P. PMID:11053130

Babes, A; Fendler, K

2000-01-01

325

Na/Ca Exchange and Na/K-ATPase Function Are Equally Concentrated in Transverse Tubules of Rat Ventricular Myocytes  

PubMed Central

Formamide-induced detubulation of rat ventricular myocytes was used to investigate the functional distribution of the Na/Ca exchanger (NCX) and Na/K-ATPase between the t-tubules and external sarcolemma. Detubulation resulted in a 32% decrease in cell capacitance, whereas cell volume was unchanged. Thus, the surface-to-volume ratio was used to assess the success of detubulation. NCX current (INCX) and Na/K pump current (Ipump) were recorded using whole-cell patch clamp, as Cd-sensitive and K-activated currents, respectively. Both inward and outward INCX density was significantly reduced by ?40% in detubulated cells. INCX density at 0 mV decreased from 0.19 ± 0.03 to 0.10 ± 0.03 pA/pF upon detubulation. Ipump density was also lower in detubulated myocytes over the range of voltages (?50 to +100 mV) and internal [Na] ([Na]i) investigated (7–22 mM). At [Na]i = 10 mM and ?20 mV, Ipump density was reduced by 39% in detubulated myocytes (0.28 ± 0.02 vs. 0.17 ± 0.03 pA/pF), but the apparent Km for [Na]i was unchanged (16.9 ± 0.4 vs. 17.0 ± 0.3 mM). These results indicate that although thet-tubules represent only ?32% of the total sarcolemma, they contribute ?60% to the total INCX and Ipump. Thus, the functional density of NCX and Na/K pump in the t-tubules is 3–3.5-fold higher than in the external sarcolemma. PMID:14581240

Despa, S.; Brette, F.; Orchard, C. H.; Bers, D. M.

2003-01-01

326

Early Age Strength and Workability of Slag Pastes Activated by NaOH and Na 2CO 3  

Microsoft Academic Search

This paper reports the results of an investigation on activation of blast furnace slag with the emphasis on achievement of equivalent one-day strength to Portland cement at normal curing temperatures and reasonable workability. The effects of varying dosages of activators NaOH and Na2CO3 are discussed in terms of strength of mini cylinders and also workability by the mini slump method.

F. Collins; J. G. Sanjayan

1998-01-01

327

NaCl Taste Thresholds in 13 Inbred Mouse Strains  

PubMed Central

Molecular mechanisms of salty taste in mammals are not completely understood. We use genetic approaches to study these mechanisms. Previously, we developed a high-throughput procedure to measure NaCl taste thresholds, which involves conditioning mice to avoid LiCl and then examining avoidance of NaCl solutions presented in 48-h 2-bottle preference tests. Using this procedure, we measured NaCl taste thresholds of mice from 13 genealogically divergent inbred stains: 129P3/J, A/J, BALB/cByJ, C3H/HeJ, C57BL/6ByJ, C57BL/6J, CBA/J, CE/J, DBA/2J, FVB/NJ, NZB/BlNJ, PWK/PhJ, and SJL/J. We found substantial strain variation in NaCl taste thresholds: mice from the A/J and 129P3/J strains had high thresholds (were less sensitive), whereas mice from the BALB/cByJ, C57BL/6J, C57BL/6ByJ, CE/J, DBA/2J, NZB/BINJ, and SJL/J had low thresholds (were more sensitive). NaCl taste thresholds measured in this study did not significantly correlate with NaCl preferences or amiloride sensitivity of chorda tympani nerve responses to NaCl determined in the same strains in other studies. To examine whether strain differences in NaCl taste thresholds could have been affected by variation in learning ability or sensitivity to toxic effects of LiCl, we used the same method to measure citric acid taste thresholds in 4 inbred strains with large differences in NaCl taste thresholds but similar acid sensitivity in preference tests (129P3/J, A/J, C57BL/6J, and DBA/2J). Citric acid taste thresholds were similar in these 4 strains. This suggests that our technique measures taste quality–specific thresholds that are likely to represent differences in peripheral taste responsiveness. The strain differences in NaCl taste sensitivity found in this study provide a basis for genetic analysis of this phenotype. PMID:22293936

Ishiwatari, Yutaka

2012-01-01

328

A kinetic analysis of Na-Li countertransport in human red blood cells  

PubMed Central

We examined the kinetic properties of the interactions between inner and outer cation sites of the Na-Li countertransport system in human red blood cells. Li-stimulated Na efflux [V(Na)] was measured as a function of external Li [(Li)o] and internal Na [(Na)i] contents. At each (Li)o, a Hanes plot of (Na)i/V(Na) vs. (Na)i allowed us to calculate the apparent dissociation constant for internal Na (KiNa) and the maximal rate of Na efflux [Vmax(Na)]. In erythrocytes from 10 different subjects, the Vmax(Na)/KiNa ratios were independent of the external Li concentrations. In other experiments, Na-stimulated Li efflux [V(Li)] was measured as a function of external Na and internal Li contents. In three subjects studied, the Vmax(Li)/KiLi ratios were independent of the external Na concentrations. The data strongly suggest that the countertransport mechanism is consecutive ("ping- pong"). PMID:2420916

1986-01-01

329

Requirement of the Na+/H+ exchanger for tumor growth.  

PubMed

The Na+/H+ exchanger is involved in a variety of cellular processes, including regulation of intracellular pH and possibly the control of cell growth and proliferation. To study the role of the Na+/H+ exchanger in tumor growth, human sodium proton exchanger-deficient (HSPD) mutants were derived from the human bladder carcinoma cell line MGH-U1 (EJ) by the proton suicide selection technique (J. Pouyssegur et al., Proc. Natl. Acad. Sci. USA, 81: 4833-4837, 1984). The HSPD cells were approximately 40% larger and contained approximately 70% more DNA than the parental cells. They were unable to grow in vitro in the absence of bicarbonate at pH less than 7.0, whereas the parental cells grew well at pH greater than or equal to 6.6. This difference in acid sensitivity was abolished in the presence of bicarbonate. In contrast to the parental MGH-U1 cells, the Na+/H+-deficient HSPD cells either failed to grow tumors, or showed severely retarded tumor growth when implanted into immune-deprived mice. This difference in tumor growth was not attributed to differences in cell size and DNA content, because Na+/H+ exchange-competent large cells (HLC), derived during the same proton suicide selection process as the HSPD cells, grew tumors at a rate close to that of the parental cells. Cells derived from the few tumors which grew after implantation of HSPD mutant cells were revertants which had regained Na+/H+ activity. HSPD cells also failed to form spheroids in culture, and the only spheroid formed consisted of revertant cells which had regained both Na+/H+ exchange activity and tumorigenic capacity. These results suggest that the Na+/H+ exchanger is important for tumor growth. PMID:2535690

Rotin, D; Steele-Norwood, D; Grinstein, S; Tannock, I

1989-01-01

330

Increased Na/H antiporter and Na/3HCO3 symporter activities in chronic hyperfiltration. A model of cell hypertrophy  

PubMed Central

The effect of chronic hyperfiltration, a model of cell hypertrophy, on H/HCO3 transporters was examined in the in vivo microperfused rat proximal tubule. Hyperfiltration was induced by uninephrectomy with subsequent increased dietary protein. After 2 wk the hyperfiltration group had a higher glomerular filtration rate (2.21 +/- 0.13 vs. 1.48 +/- 0.12 ml/min), associated with increased kidney weight (1.71 +/- 0.05 vs. 1.23 +/- 0.04 g). HCO3 absorptive rate measured in tubules perfused with an ultrafiltrate-like solution (25 mM HCO3) was higher in the hyperfiltration group (183 +/- 17 vs. 109 +/- 16 pmol/mm per min). The activities of the apical membrane Na/H antiporter and basolateral membrane Na/3HCO3 symporter were assayed using the measurement of cell pH [(2'7')-bis(carboxyethyl)-(5,6)-carboxyfluorescein] in the doubly microperfused tubule in the absence of contact with native fluids. After 2 wk of hyperfiltration Na/H antiporter activity, assayed as the effect of luminal Na removal on cell pH, was increased 114%. Basolateral membrane Na/3HCO3 symporter activity, assayed as the effect of a decrease in peritubular [HCO3] (25 to 5 mM) or in peritubular [Na] (147 to 25 mM) in the absence of luminal and peritubular chloride, was increased 77 and 113%, respectively, in the hyperfiltration group. Steady-state cell pH, measured with physiologic, ultrafiltrate-like luminal and peritubular perfusates, was significantly higher in the hyperfiltration group (7.27 +/- 0.02 vs. 7.14 +/- 0.03). In similar studies, performed 24 h after uninephrectomy and protein feeding, kidney weight was increased 10%, Na/H antiporter activity 39%, and Na/3HCO3 symporter activity 46%. At this time cell pH was not different between the two groups. The results demonstrate that chronic hyperfiltration is associated with parallel increases in Na/H antiporter and Na/3HCO3 symporter activities. If a decrease in cell pH is the signal that triggers these adaptations, it occurs early, and the adaptations can be maintained in the absence of sustained cell acidification. PMID:1849958

1991-01-01

331

El presidente Obama anuncia nombramiento del doctor Harold Varmus  

Cancer.gov

En los últimos cinco años como director del NCI, y en otras funciones ejercidas durante muchos años, he disfrutado ampliamente cada oportunidad que he tenido de visitar los laboratorios y las oficinas, desde Bethesda hasta Frederick, para conocer en persona a los miembros del personal y compartir mis opiniones sobre temas importantes en torno a la ciencia y al manejo de este gran Instituto.

332

Decoding F508del Misfolding in Cystic Fibrosis  

PubMed Central

The functional deficiency of the cystic fibrosis transmembrane conductance regulator (CFTR), a plasma membrane chloride channel, leads to the development of cystic fibrosis. The deletion of a phenylalanine at residue 508 (F508del) is the most common cause of CFTR misfolding leading to the disease. The F508del misfolding originates in the first nucleotide-binding domain (NBD1), which induces a global conformational change in CFTR through NBD1’s interactions with other domains. Such global misfolding produces a mutant chloride channel that is impaired in exocytic trafficking, peripheral stability, and channel gating. The nature and atomic details of F508del misfolding have been subject to extensive research during the past decade. Current data support a central role for NBD1 in F508del misfolding and rescue. Many cis-acting NBD1 second-site mutations rescue F508del misfolding in the context of full-length CFTR. While some of these mutations appear to specifically counteract the F508del-induced misfolding, others release certain inherent conformational constraints of the human wild-type CFTR. Several small-molecule correctors were recently found to act on key interdomain interfaces of F508del CFTR. Potential rational approaches have been proposed in an attempt to develop highly effective small molecule modulators that improve the cell surface functional expression of F508del CFTR. PMID:24970227

Wang, Xiaodong Robert; Li, Chenglong

2014-01-01

333

Paso del Norte Watershed Council Coordinated Water Resources Database Project  

E-print Network

cooperative database project that would provide streamlined access to a range of water resource data in the Paso del Norte region. In August of 2002, the El Paso Water Utilities provided initial funding to the Paso del Norte Watershed Council to develop a...

Brown, Christopher; Sheng, Zhuping; Rich, Matt

334

Hoja informativa sobre la calidad del aire interior  

E-print Network

· Moho · Polen · Caspa del pelo de los animales · Humo secundario del tabaco · Formaldehído · Monóxido de deshumidificador para ayudar a controlar el moho. · Limpie para eliminar el polvo y el pelo de los animales

335

ATTIVIT SPORTIVE DEL POLITECNICO 2 Trofeo dei Poli regionali  

E-print Network

Leonardo, la parigina Eleonore Delattre studentessa Erasmus di Design, Marco Ferrario di Architettura della 36a Course Croisiere Edhec nella rada di Brest. Ecco i partecipanti, tutti del Politecnico: Marco Lecco fra la rappresentativa del Polo di Como (in blu) e Leonardo, poi vincitore con i `Biggols'. Altre

336

Pastoral del Nino: Bringing the Abundant Life to Paraguayan Children  

ERIC Educational Resources Information Center

Pastoral del Nino is transforming children's lives in rural Paraguay. Part of Pastoral Social (Catholic Social Services), Pastoral del Nino's primary focus is to bring "vida en abundancia" (the abundant life) to families by ensuring that mothers survive childbirth and children reach their first birthdays. In addition, the organization promotes…

Austin, Ann Berghout; Aquino, Cyle; Burro, Elizabeth

2007-01-01

337

Entornos generosos para el crimen: Analisis del narcotrafico en Colombia  

Microsoft Academic Search

El objetivo de este trabajo es explicar el éxito de la industria de las drogas ilegales en Colombia mediante el concepto de «generosidad del entorno». La industria de las drogas ilegales en Colombia se puede considerar exitosa porque los narcotraficantes colombianos han: (i) movilizado altas cantidades de cocaína alrededor del mundo, (ii) generado altos niveles de recursos financieros y (iii)

Isaac Beltrán y Eduardo Salcedo-Albarán; Isaac Beltrán; Eduardo Salcedo-Albarán

2007-01-01

338

Luchando infructuosamente contra la hidra: un modelo sencillo del narcotráfico  

Microsoft Academic Search

En este artículo se presenta un modelo sencillo del narcotráfico que incorpora los riesgos de esta actividad. El modelo contribuye a explicar dos características notables del narcotráfico: la generación de ganancias extraordinarias y la gran capacidad de reproducción en condiciones de prohibición y represión. El modelo genera una relación directa entre la represión a la oferta –la estrategia dominante de

2002-01-01

339

I CONGRESO INTERNACIONAL DEL AGUA .... por la vida  

E-print Network

I CONGRESO INTERNACIONAL DEL AGUA .... por la vida Jueves 09 y viernes 10 de junio de 2005/Ciudad. Temática: Riesgos y agua. Hacia una redefinición del riesgo para una mejor gestión social. Julien Rebotier (IHEAL), Paris 3 ­ Sorbonne Nouvelle. Los riesgos socionaturales y el agua, un enfoque renovado para una

Paris-Sud XI, Université de

340

Los Derechos de los Pacientes del Centro Clnico  

E-print Network

Los Derechos de los Pacientes del Centro Clínico Los Derechos de los Pacientes del Centro Clínico medir las respuestas de los pacientes al tratamiento. Existen procesos que protegen los derechos de paciente que se observen los derechos fundamentales de la dignidad humana. Esta Declaración de Derechos

341

[The reaction mechanism of Na, K-ATPase].  

PubMed

To help characterize the Na,K-ATPase active site with enzyme incorporated into phospholipid vesicles, the activities with alternative substrates were compared, 22Na/Na-transport was equivalent with ATP, CTP, carbamylphosphate and acetylphosphate, but slower with CTP, 3-O-methylfluoresceinphosphate (3-O-MFP), nitrophenylphosphate and umbelliferonephosphate. It indicates a slower rate of formation of phosphorylating enzyme complex in conformation position of E1 (E1P) when the second group of substrates is bound with enzyme active center. 22Na/K-transport was half as effective with CTP as with ATP and was far slower with the other substrates. It indicates a more stringent selectivity at the low-affinity site of enzyme in conformation E2 that accelerates the slow step of this transport mode. Although enzyme modification with fluoresceinisothiocyanate blocks the high-affinity site to ATP, the K-phosphatase reaction catalyzed by E2 is retained, even with a substrate, 3-O-MFP, that binds to the adenine pocket. Dimethylsulfoxide inhibits hydrolysis of the nucleotides and of the carboxylic phosphate substrates of the K-phosphatase reaction, but stimulates hydrolysis of the phenolic phosphate substrates (nitrophenylphosphate and umbelliferone phosphate) which normally are hydrolyzed more slowly than the other substrates. On the basis of these data the authors propose the model of Na,K-ATPase active center. PMID:2169914

Robinson, J D; Guerra, M; Davis, R L; Steinberg, M

1990-01-01

342

Links between hydrothermal environments, pyrophosphate, na(+), and early evolution.  

PubMed

The discovery that photosynthetic bacterial membrane-bound inorganic pyrophosphatase (PPase) catalyzed light-induced phosphorylation of orthophosphate (Pi) to pyrophosphate (PPi) and the capability of PPi to drive energy requiring dark reactions supported PPi as a possible early alternative to ATP. Like the proton-pumping ATPase, the corresponding membrane-bound PPase also is a H(+)-pump, and like the Na(+)-pumping ATPase, it can be a Na(+)-pump, both in archaeal and bacterial membranes. We suggest that PPi and Na(+) transport preceded ATP and H(+) transport in association with geochemistry of the Earth at the time of the origin and early evolution of life. Life may have started in connection with early plate tectonic processes coupled to alkaline hydrothermal activity. A hydrothermal environment in which Na(+) is abundant exists in sediment-starved subduction zones, like the Mariana forearc in the W Pacific Ocean. It is considered to mimic the Archean Earth. The forearc pore fluids have a pH up to 12.6, a Na(+)-concentration of 0.7 mol/kg seawater. PPi could have been formed during early subduction of oceanic lithosphere by dehydration of protonated orthophosphates. A key to PPi formation in these geological environments is a low local activity of water. PMID:21461648

Holm, Nils G; Baltscheffsky, Herrick

2011-10-01

343

Na+/H+ Antiport Is Essential for Yersinia pestis Virulence  

PubMed Central

Na+/H+ antiporters are ubiquitous membrane proteins that play a central role in the ion homeostasis of cells. In this study, we examined the possible role of Na+/H+ antiport in Yersinia pestis virulence and found that Y. pestis strains lacking the major Na+/H+ antiporters, NhaA and NhaB, are completely attenuated in an in vivo model of plague. The Y. pestis derivative strain lacking the nhaA and nhaB genes showed markedly decreased survival in blood and blood serum ex vivo. Complementation of either nhaA or nhaB in trans restored the survival of the Y. pestis nhaA nhaB double deletion mutant in blood. The nhaA nhaB double deletion mutant also showed inhibited growth in an artificial serum medium, Opti-MEM, and a rich LB-based medium with Na+ levels and pH values similar to those for blood. Taken together, these data strongly suggest that intact Na+/H+ antiport is indispensable for the survival of Y. pestis in the bloodstreams of infected animals and thus might be regarded as a promising noncanonical drug target for infections caused by Y. pestis and possibly for those caused by other blood-borne bacterial pathogens. PMID:23774602

Minato, Yusuke; Ghosh, Amit; Faulkner, Wyatt J.; Lind, Erin J.; Schesser Bartra, Sara; Plano, Gregory V.; Jarrett, Clayton O.; Hinnebusch, B. Joseph; Winogrodzki, Judith; Dibrov, Pavel

2013-01-01

344

Kinetic comparisons of heart and kidney Na+,K(+)-ATPases.  

PubMed

Most kinetic measurements of the partial reactions of Na(+),K(+)-ATPase have been conducted on enzyme from mammalian kidney. Here we present a kinetic model that is based on the available equilibrium and kinetic parameters of purified kidney enzyme, and allows predictions of its steady-state turnover and pump current in intact cells as a function of ion and ATP concentrations and the membrane voltage. Using this model, we calculated the expected dependence of the pump current on voltage and extracellular Na(+) concentration. The simulations indicate a lower voltage dependence at negative potentials of the kidney enzyme in comparison with heart muscle Na(+),K(+)-ATPase, in agreement with experimental results. The voltage dependence is enhanced at high extracellular Na(+) concentrations. This effect can be explained by a voltage-dependent depopulation of extracellular K(+) ion binding sites on the E2P state and an increase in the proportion of enzyme in the E1P(Na(+))(3) state in the steady state. This causes a decrease in the effective rate constant for occlusion of K(+) by the E2P state and hence a drop in turnover. Around a membrane potential of zero, negligible voltage dependence is observed because the voltage-independent E2(K(+))(2) ? E1 + 2K(+) transition is the major rate-determining step. PMID:22947929

Garcia, Alvaro; Rasmussen, Helge H; Apell, Hans-Jürgen; Clarke, Ronald J

2012-08-22

345

Na[superscript +] binding to meizothrombin desF1  

SciTech Connect

Meizothrombin is the physiologically active intermediate generated by a single cleavage of prothrombin at R320 to separate the A and B chains. Recent evidence has suggested that meizothrombin, like thrombin, is a Na{sup +}-activated enzyme. In this study we present the first X-ray crystal structure of human meizothrombin desF1 solved in the presence of the active site inhibitor PPACK at 2.1 {angstrom} resolution. The structure reveals a Na{sup +} binding site whose architecture is practically identical to that of human thrombin. Stopped-flow measurements of Na{sup +} binding to meizothrombin desF1 document a slow phase of fluorescence change with a k obs decreasing hyperbolically with increasing [Na{sup +}], consistent with the existence of three conformations in equilibrium, E*, E and E:Na{sup +}, as for human thrombin. Evidence that meizothrombin exists in multiple conformations provides valuable new information for studies of the mechanism of prothrombin activation.

Papaconstantinou, M.E.; Gandhi, P.S.; Chen, Z.; Bah, A.; Di Cera, E. (WU-MED)

2009-06-10

346

Ouabain Binding Site in a Functioning Na+/K+ ATPase*  

PubMed Central

The Na+/K+ ATPase is an almost ubiquitous integral membrane protein within the animal kingdom. It is also the selective target for cardiotonic derivatives, widely prescribed inhibitors for patients with heart failure. Functional studies revealed that ouabain-sensitive residues distributed widely throughout the primary sequence of the protein. Recently, structural work has brought some consensus to the functional observations. Here, we use a spectroscopic approach to estimate distances between a fluorescent ouabain and a lanthanide binding tag (LBT), which was introduced at five different positions in the Na+/K+ ATPase sequence. These five normally functional LBT-Na+/K+ ATPase constructs were expressed in the cell membrane of Xenopus laevis oocytes, operating under physiological internal and external ion conditions. The spectroscopic data suggest two mutually exclusive distances between the LBT and the fluorescent ouabain. From the estimated distances and using homology models of the LBT-Na+/K+ ATPase constructs, approximate ouabain positions could be determined. Our results suggest that ouabain binds at two sites along the ion permeation pathway of the Na+/K+ ATPase. The external site (low apparent affinity) occupies the same region as previous structural findings. The high apparent affinity site is, however, slightly deeper toward the intracellular end of the protein. Interestingly, in both cases the lactone ring faces outward. We propose a sequential ouabain binding mechanism that is consistent with all functional and structural studies. PMID:21911500

Sandtner, Walter; Egwolf, Bernhard; Khalili-Araghi, Fatemeh; Sanchez-Rodriguez, Jorge E.; Roux, Benoit; Bezanilla, Francisco; Holmgren, Miguel

2011-01-01

347

Schistosome Na,K-ATPase as a therapeutic target.  

PubMed

Na,K-ATPases are ubiquitous membrane-bound enzymes comprising ? and ? subunits. Here we clone a Na,K-ATPase ? homolog (designated SNaK1?) from the human parasitic platyhelminth, Schistosoma mansoni. The predicted protein is about 33 kDa, and contains a single transmembrane domain and multiple conserved motifs. SNaK1? and its previously cloned ?-subunit counterpart (SNaK1?) are both expressed throughout the schistosome life cycle. In adults, both subunits are detected in the tegumental membrane, likely functioning at the host-parasite interface in Na/K exchange. Both SNaK1 genes can be suppressed by RNAi using target-specific small inhibitory RNAs (siRNAs), and this severely debilitates the parasites both in vitro and in vivo. However, treating schistosomiasis by delivering the siRNAs hydrodynamically to infected mice has no detectable impact on worms. Additionally, treating schistosome-infected mice with the Na,K-ATPase inhibitor, ouabain, is ineffective. Nonetheless, since schistosomes are very susceptible to perturbation in SNaK1 expression, further work to identify other Na,K-ATPase inhibitors as anti-schistosome agents is warranted. PMID:23222953

Da'dara, Akram A; Faghiri, Zahra; Krautz-Peterson, Greice; Bhardwaj, Rita; Skelly, Patrick J

2013-02-01

348

Links Between Hydrothermal Environments, Pyrophosphate, Na+, and Early Evolution  

NASA Astrophysics Data System (ADS)

The discovery that photosynthetic bacterial membrane-bound inorganic pyrophosphatase (PPase) catalyzed light-induced phosphorylation of orthophosphate (Pi) to pyrophosphate (PPi) and the capability of PPi to drive energy requiring dark reactions supported PPi as a possible early alternative to ATP. Like the proton-pumping ATPase, the corresponding membrane-bound PPase also is a H+-pump, and like the Na+-pumping ATPase, it can be a Na+-pump, both in archaeal and bacterial membranes. We suggest that PPi and Na+ transport preceded ATP and H+ transport in association with geochemistry of the Earth at the time of the origin and early evolution of life. Life may have started in connection with early plate tectonic processes coupled to alkaline hydrothermal activity. A hydrothermal environment in which Na+ is abundant exists in sediment-starved subduction zones, like the Mariana forearc in the W Pacific Ocean. It is considered to mimic the Archean Earth. The forearc pore fluids have a pH up to 12.6, a Na+-concentration of 0.7 mol/kg seawater. PPi could have been formed during early subduction of oceanic lithosphere by dehydration of protonated orthophosphates. A key to PPi formation in these geological environments is a low local activity of water.

Holm, Nils G.; Baltscheffsky, Herrick

2011-10-01

349

Biosensor Consists of Na -- Doped Hydroxyapatite Thin Film  

NASA Astrophysics Data System (ADS)

Hydroxyapatite (HAp) surface has an excellent ability of adsorption for functional biomolecules such as protein, DNA and so on. We have investigated the application of the HAp as a suitable material for biosensor. Thin film of the sodium -- doped HAp (Na -- HAp) is prepared in order to decrease the electric resistivity. We have studied variation of the resistance for the Na -- HAp thin films with the adsorption of the functional biomolecules. The sample were prepared by a pulsed laser deposition technique on porous alumina substrate. After the deposition, sample was post -- annealed in O2 / H2O atmosphere in order to crystallize the Na -- HAp. The powder X ray diffraction pattern shows the sample has a pure HAp structure. The gold comb electrodes were evaporated on the sample for the resistance measurement. The sample was set in pure water of 100 ml in a beaker. When Fetal Bovine Serum of 100 ?l was dropped in the beaker, the Na -- HAp shows the drastic change of the AC resistance (at 120 kHz). This result shows that the Na -- HAp will be one of the most effective materials for the biosensor applications.

Nishikawa, Hiroaki; Kawashima, Masami; Kawai, Tomoji

2005-03-01

350

Highly bright multicolor tunable ultrasmall ?-Na(Y,Gd)F?:Ce,Tb,Eu/?-NaYF? core/shell nanocrystals.  

PubMed

Herein, we report highly bright multicolor-emitting ?-Na(Y,Gd)F?:Ce,Tb,Eu/?-NaYF? nanoparticles (NPs) with precise color tunability. First, highly bright sub-20 nm ?-Na(Y,Gd)F?:Ce,Tb,Eu NPs were synthesized via a heating-up method. By controlling the ratio of Eu(3+) to Tb(3+), we generated green, yellow-green, greenish yellow, yellow, orange, reddish orange, and red emissions from the NP solutions via energy transfer of Ce(3+)? Gd(3+)? Tb(3+) (green) and Ce(3+)? Gd(3+)? Tb(3+)? Eu(3+) (red) ions under ultraviolet light illumination (254 nm). Because of Ce(3+) and Gd(3+) sensitization, Tb(3+) ions exhibited strong green emission. The decay time of Tb(3+) emission decreased from 4.0 to 1.4 ms as the Eu(3+) concentration was increased, suggesting that energy was transferred from Tb(3+) to Eu(3+). As a result, Eu(3+) emission peaks were generated and the emission color was transformed from green to red. Monodisperse sub-6 nm ?-Na(Y,Gd)F?:Ce,Tb,Eu NPs were synthesized through a simple reduction of the reaction temperature. Although fine color tunability was retained, their brightness was considerably decreased owing to an increase in the surface-to-volume ratio. The formation of a ?-NaYF? shell on top of the sub-6 nm NP core to produce ?-Na(Y,Gd)F?:Ce,Tb,Eu/?-NaYF? significantly increased the emission intensity, while maintaining the sub-10 nm sizes (8.7-9.5 nm). Quantum yields of the ultrasmall NPs increased from 1.1-6.9% for the core NPs to 6.7-44.4% for the core/shell NPs. Moreover, highly transparent core/shell NP-polydimethylsiloxane (PDMS) composites featuring a variety of colors, excellent color tunability, and high brightness were also prepared. PMID:23945563

Kim, Su Yeon; Woo, Kyoungja; Lim, Kipil; Lee, Kwangyeol; Jang, Ho Seong

2013-10-01

351

The Na(+) transporter, TaHKT1;5-D, limits shoot Na(+) accumulation in bread wheat.  

PubMed

Bread wheat (Triticum aestivum L.) has a major salt tolerance locus, Kna1, responsible for the maintenance of a high cytosolic K(+) /Na(+) ratio in the leaves of salt stressed plants. The Kna1 locus encompasses a large DNA fragment, the distal 14% of chromosome 4DL. Limited recombination has been observed at this locus making it difficult to map genetically and identify the causal gene. Here, we decipher the function of TaHKT1;5-D, a candidate gene underlying the Kna1 locus. Transport studies using the heterologous expression systems Saccharomyces cerevisiae and Xenopus laevis oocytes indicated that TaHKT1;5-D is a Na(+) -selective transporter. Transient expression in Arabidopsis thaliana mesophyll protoplasts and in situ polymerase chain reaction indicated that TaHKT1;5-D is localised on the plasma membrane in the wheat root stele. RNA interference-induced silencing decreased the expression of TaHKT1;5-D in transgenic bread wheat lines which led to an increase in the Na(+) concentration in the leaves. This indicates that TaHKT1;5-D retrieves Na(+) from the xylem vessels in the root and has an important role in restricting the transport of Na(+) from the root to the leaves in bread wheat. Thus, TaHKT1;5-D confers the essential salinity tolerance mechanism in bread wheat associated with the Kna1 locus via shoot Na(+) exclusion and is critical in maintaining a high K(+) /Na(+) ratio in the leaves. These findings show there is potential to increase the salinity tolerance of bread wheat by manipulation of HKT1;5 genes. PMID:25158883

Byrt, Caitlin Siobhan; Xu, Bo; Krishnan, Mahima; Lightfoot, Damien James; Athman, Asmini; Jacobs, Andrew Keith; Watson-Haigh, Nathan S; Plett, Darren; Munns, Rana; Tester, Mark; Gilliham, Matthew

2014-11-01

352

NaOH Recovery from MEROX Tower Waste Stream Using the Electrodialysis Process  

Microsoft Academic Search

Electrodialysis with two different configurations was used for the recovery of NaOH from the waste stream of a MEROX tower. For this purpose, the effects of cell applied voltage and initial Na concentration in the feed solution on NaOH recovery and current efficiency were studied. Results showed that the recovery and current efficiency were improved by increasing the initial Na

Narjes Keramati; Ahmad Moheb; Mohammad Reza Ehsani

2010-01-01

353

Molecular analysis of the Na+ channel blocking actions of the novel  

E-print Network

Molecular analysis of the Na+ channel blocking actions of the novel class I anti-arrhythmic agent of the Na+ channel, and that the drug may produce potent local anaesthetic or anti-arrhythmic action under; RSD 921; class I anti-arrhythmic; Xenopus oocytes; Na+ channel Abbreviations: rBIIA, rat brain IIA Na

Goldin, Alan L.

354

Molecular basis of DEL phenotype in the Chinese population  

PubMed Central

Background Rh blood group system is the most complex and immunogenetic blood group system. Prevalent RHD alleles vary in different populations. We conducted the present study to examine the genotype of DEL individuals and to elucidate whether novel alleles exist in the Chinese population. Methods DEL phenotype was identified by a serologic adsorption-elution method. The nucleotide sequences of ten RHD exons and exon-intron boundary regions were evaluated by RHD gene-specific PCR-SSP and sequencing. Results Of 42306 samples from individual donors and patients, 165 samples were typed as D-negative. Among these D-negative samples, 41 DEL individuals were observed. Thirty-seven DELs were confirmed to have the RHD1227A allele. Two DELs seemed to have RHD-CE-D hybrid alleles, including one RHD-CE (4–7)-D and one RHD-CE (2–5)-D. Two novel RHD alleles were found among the rest of the DEL samples, including one RHD93T?>?A and one RHD838G?>?A. Conclusion In this study, about 24.85% (41/165) of the apparent D-negative Chinese individuals were DEL. RHD1227G?>?A is the most frequent allele in Chinese DEL phenotypes, accounting for 90.24% (37/41). The RHD-CE-D hybrid allele might be the second most frequent DEL allele in the Chinese population. Our study would contribute to the understanding of the molecular mechanism underlying D antigen expression of DEL individuals and provide useful information for designing suitable genotyping strategies in RhD-negative individuals in Asia. PMID:24884404

2014-01-01

355

Publicaciones del IGME: serie Hidrogeologa y aguas subterrneas, n 14. VI Simposio del Agua en Andaluca. I: 619-628. 2005  

E-print Network

Publicaciones del IGME: serie Hidrogeología y aguas subterráneas, nº 14. VI Simposio del Agua en) , Benavente Herrera, José(2) e Hidalgo Estévez, Mª del Carmen(3) (1) CSIC e Instituto del Agua (Univ. Granada). C/ Ramón y Cajal, 4. 18071Granada. Correo electrónico: acastill@ugr.es (2) Instituto del Agua (Univ

Castillo, Antonio

356

Growth and electronic properties of NaCl on HOPG  

NASA Astrophysics Data System (ADS)

We report the growth of cross-shaped islands of NaCl on highly oriented pyrolytic graphite (HOPG) and discuss the mechanism of formation and growth kinetics within the framework of diffusion limited aggregation (DLA). These structures are investigated using scanning probe microscopy. The shape and structure of these islands can be finely controlled by the deposition conditions. The islands exhibit large atomically flat surfaces which are ideal supports for investigations of the fundamental properties of deposited atoms, molecules or clusters. Bismuth nanostructures were deposited on the NaCl islands and were investigated via scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS). The tunneling spectra recorded for particles on NaCl are surprisingly similar to those measured for similar particles on HOPG. We suggest that this is due to a 'dead' layer commonly observed for Bi thin films.

Mahapatra, O.; Kowalczyk, P. J.; Brown, S. A.

2014-02-01

357

HARP and NA61 (SHINE) hadron production experiments  

SciTech Connect

The hadroproduction experiments HARP and NA61 (SHINE) as well as their implications for neutrino physics are discussed. Recent HARP measurements have already been used for precise predictions of neutrino beams in K2K and MiniBooNE/SciBooNE experiments and are also being used to improve the atmospheric neutrino flux predictions and to help in the optimization of neutrino factory and super-beam designs. First preliminary data from NA61 are of significant importance for a precise prediction of a new neutrino beam at J-PARC to be used for the first stage of the T2K experiment. Both HARP and NA61 provide a large amount of input for validation and tuning of hadroproduction models in Monte-Carlo generators.

Popov, Boris A. [LPNHE, 4 place Jussieu, 75005, Paris and DLNP, JINR, Joliot-Curie 6, 141980, Dubna (Russian Federation)

2009-11-25

358

Intrinsic energy resolution of NaI(Tl)1  

NASA Astrophysics Data System (ADS)

The light output for ?10 mm×10 mm and ?75 mm×75 mm NaI(Tl) crystals and energy resolution were measured for ?-ray energies ranging from 16-1333 keV. These measurements enabled the observation of the light yield nonproportionality behavior and allowed the determination of the intrinsic resolution after correcting for the measured resolution for photomultiplier tube (PMT) statistics. The intrinsic resolution was then compared with the nonproportionality component. The latter was calculated using measured electron response, Monte Carlo N Particle code (MCNP4B), and the simplified cascade sequence for NaI(Tl). This comparison allowed the identification of the intrinsic resolution component associated with ?-rays. Consequently, it was shown that the ?-ray component is the most dominant component of the NaI(Tl) intrinsic resolution.

Moszy?ski, M.; Zalipska, J.; Balcerzyk, M.; Kapusta, M.; Mengesha, W.; Valentine, J. D.

2002-05-01

359

Characterization of the Na?/H? antiporter from Yersinia pestis.  

PubMed

Yersinia pestis, the bacterium that historically accounts for the Black Death epidemics, has nowadays gained new attention as a possible biological warfare agent. In this study, its Na?/H? antiporter is investigated for the first time, by a combination of experimental and computational methodologies. We determined the protein's substrate specificity and pH dependence by fluorescence measurements in everted membrane vesicles. Subsequently, we constructed a model of the protein's structure and validated the model using molecular dynamics simulations. Taken together, better understanding of the Yersinia pestis Na?/H? antiporter's structure-function relationship may assist in studies on ion transport, mechanism of action and designing specific blockers of Na?/H? antiporter to help in fighting Yersinia pestis -associated infections. We hope that our model will prove useful both from mechanistic and pharmaceutical perspectives. PMID:22102858

Ganoth, Assaf; Alhadeff, Raphael; Kohen, Dovrat; Arkin, Isaiah T

2011-01-01

360

Superconducting properties and electronic structure of NaBi.  

PubMed

Resistivity, dc magnetization, and heat capacity measurements are reported for superconducting NaBi. T(c), the electronic contribution to the specific heat ?, the ?C(p)/?T(c) ratio, and the Debye temperature are found to be 2.15?K, 3.4?mJ?mol(-1)?K(-2), 0.78, and 140?K respectively. The calculated electron-phonon coupling constant (?(ep) = 0.62) implies that NaBi is a moderately coupled superconductor. The upper critical field and coherence length are found to be 250?Oe and 115?nm, respectively. Electronic structure calculations show NaBi to be a good metal, in agreement with the experiments; the p(x) and p(y) orbitals of Bi dominate the electronic states at the Fermi Energy. PMID:24804822

Kushwaha, S K; Krizan, J W; Xiong, J; Klimczuk, T; Gibson, Q D; Liang, T; Ong, N P; Cava, R J

2014-05-28

361

Llamado a cubrir Beca de investigacin. Uso del agua en Sistemas de Produccin Agrcola del Chaco Semirido.  

E-print Network

Llamado a cubrir Beca de investigación. Uso del agua en Sistemas de Producción Agrícola del Chaco agua en sistemas de producción agrícola en el Chaco Semiárido mediante modelos funcionales de cultivo

Nacional de San Luis, Universidad

362

Declaración del Instituto Nacional del Cáncer sobre la aprobación de la vacuna de VPH por la FDA  

Cancer.gov

Hace casi dos décadas que los investigadores del NCI y de otras instituciones comenzaron a investigar las causas fundamentales del cáncer cervical. Esta búsqueda científica resultó en la aprobación de hoy de la vacuna GardasilTM por la Food and Drug Administration.

363

High-NA HPCS optical fibers for medical diagnosis and treatment  

NASA Astrophysics Data System (ADS)

Hard Plastic Clad Silica (HPCS) optical fibers with pure silica cores have been developed which are robust and have NA(Numerical Aperture)>0.50. Improved clad only HPCS fibers have been produced for both new 'standard' and 'high' NA versions. Based on new cladding formulations, the 'standard' NA fiber has an NA of 0.41, while the new ultrahigh NA fiber has an NA of 0.54. Mechanical strength and preliminary fatigue data are presented along with spectral characterization data. For the first time significant results were obtained for clad only high NA fibers, The fibers are useful for diagnostic and surgical applications. Short to medium length time to failure results, indicate that the static fatigue parameters of the new high numerical aperture (NA) optical fibers are at least as good as those for former standard NA (0.37) HPCS fibers, which is an advance from previous results on the older formulation high NA fibers.

Skutnik, Bolesh J.

2010-02-01

364

Electrogenic 2 Na+/1 H+ exchange in crustaceans.  

PubMed

Hepatopancreatic brush border membrane vesicles of the freshwater prawn, Macrobrachium rosenbergii and the marine lobster, Homarus americanus exhibited 22Na uptake which was Cl-independent, amiloride sensitive, and stimulated by a transmembrane H gradient (Hi greater than Ho). Sodium influx by vesicles of both species were sigmoidal functions of [Na]o, yielding Hill coefficients that were not significantly different (P greater than 0.5) than 2.0. Estimations of half-saturation constants (KNa) were 82.2 mM (prawn) and 280.1 mM (lobster), suggesting a possible adaptation of this transporter to environmental salinity. Trans-stimulation and cis-inhibition experiments involving variable [H] suggested that the exchangers in both species possessed single internal cation binding sites (pK 6.5-6.7) and two external cation binding sites (prawn, pK 4.0 and 5.7; lobster pK 3.5 and 6.1). Similar cis inhibition studies using amiloride as a competitive inhibitor of Na uptake supported the occurrence of dual external sites (prawn, Ki50 and 1520 microM; lobster Ki9 and 340 microM). Electrogenic Na/H exchange by vesicles from both crustaceans was demonstrated using equilibrium shift experiments where a transmembrane potential was used as the only driving force for the transport event. Transport stoichiometries of the antiporters were determined using Static Head analysis where driving forces for cation transfer were balanced using a 10:1 Na gradient, a 100:1 H gradient, and a stoichiometry of 2.0. These electrogenic 2 Na/1 H exchangers appear thermodynamically capable of generating sufficient gastric acidification for organismic digestive activities. PMID:2167376

Ahearn, G A; Franco, P; Clay, L P

1990-07-01

365

A study of the reaction NaO2+ O ? NaO+ O2: Implications for the chemistry of sodium in the upper atmosphere  

NASA Astrophysics Data System (ADS)

Sodium superoxide (NaO2) is believed to be a major sink for meteor-ablated Na in the upper atmosphere. However, the rate constant for the reaction between NaO2 and O is not known, and its determination is the subject of this study. NaO2 was produced by the reaction between Na vapor, an excess of O2, and the carrier gas N2 in the upstream section of a fast flow tube reactor. Excess atomic O was then added, so that a steady state developed in which the sodium was partitioned between its atomic form and a variety of oxides. The steady state fraction of atomic Na, monitored by laser-induced fluorescence, was then observed as a function of [O] and [O2], from which it was deduced that k(NaO2 + O) = (2.2 ± 1.0) × 10-11 cm3 molecule-1 s-1 at 300 K (3? uncertainty). As a prelude to this experiment, the recombination reaction between O2 and Na was studied by the conventional flow tube technique, yielding k(Na + O2 + N2) = (3.14 ± 0.20) ×10-30 (300/T)-(1.52±0.27) cm6 molecule-2 s-1. These experimental results were then incorporated into a one-dimensional model of sodium in the upper atmosphere between 65 and 110 km. It is shown that formation of NaHCO3 rather than NaO2 is the dominant removal process for atomic Na below 90 km. This new model, whose only important assumption is the rate constant for the reaction NaHCO3 + H ? Na + H2CO3, predicts a seasonal variation of the atomic Na layer in excellent agreement with recent lidar observations at 40° and 69°N and also demonstrates that temperature fluctuations produced by gravity waves should induce significant chemical responses in the Na layer below 88 km.

Helmer, Magdalena; Plane, John M. C.

1993-12-01

366

Possible selective adsorption of enantiomers by Na-montmorillonite  

NASA Technical Reports Server (NTRS)

Racemic amino acids including (D,L) alpha-alamine, (D,L) alpha-aminobutyric acid, (D,L) valine, and (D,L) norvaline were incubated with Na-montmorillonite at 100% CEC at three hydrogen ion concentrations, and amino acid adsorption was determined by ion exchange chromatography. Enantiomers were analyzed by gas chromatography. Differences in the quantities of D and L enantiomers in any of the fractions was no larger than a few percent. Although a large difference in the adsorption of the amino acid enantiomers was not observed, the analysis may indicate a small preferential adsorption (0.5-2%) of L-amino acids by Na-montmorillonite.

Friebele, E.; Shimoyama, A.; Ponnamperuma, C.

1981-01-01

367

Tb/Na tobermorite: Thermal behaviour and high temperature products  

NASA Astrophysics Data System (ADS)

By heating a sample of Tb/Na tobermorite we obtained a phase which was identified through its X-ray diffraction (XRD) pattern, as terbium silicate apatite. Subsequently this compound has been directly prepared by solid state reaction and we carried out a structural refinement from XRD data in space group P6 3/ m obtaining cell parameters a=9.39199(4) Å and c=6.84041(5) Å. Terbium silicate apatite heated in melted NaF led to Tb 4O 7 crystals.

Garra, Walter; Marchetti, Fabio; Merlino, Stefano

2009-06-01

368

Supporting Information to "Influence of Salt Purity on Na+  

E-print Network

.5 1.0 1.5 2.0 decrease with time a PA on UP grade 0.6 M NaCl 10-15 min 20-25 min 35-40 min 45-50 min 55-60 min VSFGIntensity(a.u.) increase with time b PA on ACS grade 0.6 M NaCl 10-15 min 20-25 min 35-40 min 45-50 min 55-60 min VSFGIntensity(a.u.) Wavenumber (cm -1 ) 1350 1400 1450 1500 1550 1600 0.0 0

369

Structural Integrity and Microstructure of NA^+ Conducting Ceramics  

NASA Astrophysics Data System (ADS)

Oxides with the general formula of Na1+x Zr2 Six P3-x O12 , known as Nasicon, are fast Na+ ion-conducting materials with important electrochemical applications and many functional properties, often attributed to their unique structural features. Comparative, in situ studies of the limits of structural integrity were performed for selected Nasicon materials, using synchrotron x-ray diffraction and diamond anvil cell technology. We show how different processing conditions produce crystalline structures with specific morphology. We discuss the bulk modulus, the compressibility and the influence of the volume fraction of primary and secondary crystalline phases on the overall Nasicon structural integrity.

Lipinska, Kristina; Kalita, Patricia; Hemmers, Oliver; Sinogeikin, Stanislav; Shebanova, Olga; Yang, Wenge; Mariotto, Gino

2010-03-01

370

Kinetics of 9-aminoacridine block of single Na channels  

PubMed Central

The kinetics of 9-aminoacridine (9-AA) block of single Na channels in neuroblastoma N1E-115 cells were studied using the gigohm seal, patch clamp technique, under the condition in which the Na current inactivation had been eliminated by treatment with N-bromoacetamide (NBA). Following NBA treatment, the current flowing through individual Na channels was manifested by square-wave open events lasting from several to tens of milliseconds. When 9-AA was applied to the cytoplasmic face of Na channels at concentrations ranging from 30 to 100 microM, it caused repetitive rapid transitions (flickering) between open and blocked states within single openings of Na channels, without affecting the amplitude of the single channel current. The histograms for the duration of blocked states and the histograms for the duration of open states could be fitted with a single-exponential function. The mean open time (tau o) became shorter as the drug concentration was increased, while the mean blocked time (tau b) was concentration independent. The association (blocking) rate constant, kappa, calculated from the slope of the curve relating the reciprocal mean open time to 9-AA concentration, showed little voltage dependence, the rate constant being on the order of 1 X 10(7) M-1s-1. The dissociation (unblocking) rate constant, l, calculated from the mean blocked time, was strongly voltage dependent, the mean rate constant being 214 s-1 at 0 mV and becoming larger as the membrane being hyperpolarized. The voltage dependence suggests that a first-order blocking site is located at least 63% of the way through the membrane field from the cytoplasmic surface. The equilibrium dissociation constant for 9-AA to block the Na channel, defined by the relation of l/kappa, was calculated to be 21 microM at 0 mV. Both tau -1o and tau -1b had a Q10 of 1.3, which suggests that binding reaction was diffusion controlled. The burst time in the presence of 9-AA, which is the sum of open times and blocked times, was longer than the lifetime of open channels in the absence of drug. All of the features of 9-AA block of single Na channels are compatible with the sequential model in which 9-AA molecules block open Na channels, and the blocked channels could not close until 9-AA molecules had left the blocking site in the channels. PMID:6090578

1984-01-01

371

NA62 experiment: Measurement of BR(K+ ? ?+?nubar)  

NASA Astrophysics Data System (ADS)

The NA62 experiment aims to measure the very rare kaon decay K+ ? ?+?nubar at the CERN SPS. The expected branching ratio has been recently estimated within the Standard Model to be (8.22 ± 0.84) × 10-11. From the experimental side, 7 events has been found by E787/949 experiments at BNL providing a measurement of the branching ratio of (1.73+1.15-1.05) × 10-10. The aim of NA62 is to collect ~100 events in two years of data taking with a 10% background. A description of the setup and the R&D program is presented.

Cortina Gil, Eduardo

2009-06-01

372

Complex microwave conductivity of Na-DNA powders  

E-print Network

We report the complex microwave conductivity, $\\sigma=\\sigma_1-i\\sigma_2$, of Na-DNA powders, which was measured from 80 K to 300 K by using a microwave cavity perturbation technique. We found that the magnitude of $\\sigma_1$ near room temperature was much larger than the contribution of the surrounding water molecules, and that the decrease of $\\sigma_1$ with decreasing temperature was sufficiently stronger than that of the conduction of counterions. These results clearly suggest that the electrical conduction of Na-DNA is intrinsically semiconductive.

H. Kitano; K. Ota; A. Maeda

2006-08-01

373

Russian Scientific-Educational Project: Kazan-GeoNa-2017  

NASA Astrophysics Data System (ADS)

For the further successful development of educational and scientific - educational activity of the Russian Federation, the Republic Tatarstan, Kazan is offered the national project - the International Center of the Science and the Internet of Technologies. "GeoNa" (Geometry of Nature - "GeoNa" is developed - wisdom, enthusiasm, pride, grandeur), which includes a modern complex of conference halls (up to 4 thousand places), the Center the Internet of Technologies, 3D Planetarium - development of the Moon, PhysicsLand, an active museum of natural sciences, an oceanarium, training a complex «Spheres of Knowledge», botanical and landscape oases.

Gusev, A.; Alibekova, N.

2011-10-01

374

Russian Scientific-Educational Project: Kazan-GeoNa-2017  

NASA Astrophysics Data System (ADS)

For the further successful development of educational and scientific - educational activity of the Russian Federation, the Republic Tatarstan, Kazan is offered the national project - the International Center of the Science and the Internet of Technologies. "GeoNa" (Geometry of Nature - "GeoNa" is developed - wisdom, enthusiasm, pride, grandeur), which includes a modern complex of conference halls (up to 4 thousand places), the Center the Internet of Technologies, 3D Planetarium - development of the Moon, PhysicsLand, an active museum of natural sciences, an oceanarium, training a complex «Spheres of Knowledge», botanical and landscape oases.

Gusev, A.; Alibekova, N.

2012-09-01

375

Molecular dynamics simulation of dipalmitoylphosphatidylserine bilayer with Na+ counterions.  

PubMed Central

We performed a molecular dynamics simulation of dipalmitoylphosphatidylserine (DPPS) bilayer with Na+ counterions. We found that hydrogen bonding between the NH group and the phosphate group leads to a reduction in the area per headgroup when compared to the area in dipalmitoylphosphatidylcholine bilayer. The Na+ ions bind to the oxygen in the carboxyl group of serine, thus giving rise to a dipolar bilayer similar to dipalmitoylphosphatidylethanolamine bilayer. The results of the simulation show that counterions play a crucial role in determining the structural and electrostatic properties of DPPS bilayer. PMID:11916841

Pandit, Sagar A; Berkowitz, Max L

2002-01-01

376

Beta-Gamma-Angular Correlation in Na-20  

E-print Network

Station, Texas 77843 D. P. May and D. M. Tanner Cyclotron Institute, Texas A AM University, College Station, Texas 77843 (Received 19 November 1980) The P-y angular correlation for the decay of "Na has been measured using a symmetric four detector... for the two correlations, we find 2245 1981 The American Physical Society 2246 R. K. YRIBBLK, D. P. MAY, AND D. M. TANNER (5) 6165 C (7) where a'(E,)=E,("Na)+E,("F)=16.6 MeV. By invoking the conserved vector current (CVC) hypothesis, ' the weak...

Tribble, Robert E.; May, D. P.; Tanner, D. M.

1981-01-01

377

Na 2 SO 4 -induced accelerated oxidation (hot corrosion) of nickel  

Microsoft Academic Search

The Na2SO4-induced accelerated oxidation of nickel has been studied at 1000C. It has been found that low oxygen activities in the Na2SO4, which are produced by the formation of NiO, cause the sulfur activity of the Na2SO4 to be increased. Nickel and sulfur from the Na2SO4 combine to form nickel sulfide and the oxide ion activity of the Na2SO4 is

J. A. Goebel; F. S. Pettit

1970-01-01

378

Differential effects of substrates on three transport modes of the Na+/K(+)-ATPase.  

PubMed

With a purified Na+/K(+)-ATPase preparation reconstituted into phospholipid vesicles, Na+/K+, Na+/Na+, and uncoupled Na+ transport were studied using three nucleotides and five substrates of the K(+)-phosphatase reaction that this enzyme also catalyzes. For Na+/K+ exchange, CTP was half as effective as ATP and GTP one-twentieth; of the phosphatase substrates only carbamyl phosphate and 3-O-methylfluorescein phosphate produced significant transport and at merely 1% of the rate with ATP. For Na+/Na+ exchange, comparable rates of transport were produced by ATP, CTP, carbamyl phosphate and acetyl phosphate, although the actual rate of transport with ATP was only 2.4% of that for Na+/K+ exchange; slower rates occurred with GTP (69%), 3-O-methylfluorescein phosphate (51%), and nitrophenyl phosphate (33%). Only umbelliferone phosphate was ineffective. For uncoupled Na+ transport results similar to those for Na+/Na+ exchange were obtained, but the actual rate of transport was still slower, 1.4% of that for Na+/K+ exchange. Thus, not only nucleotides but a variety of phosphatase substrates (which are phosphoric acid mixed anhydrides) can phosphorylate the enzyme at the high-affinity substrate site to form the E1P intermediate of the reaction sequence. Oligomycin inhibited Na+/K+ exchange with ATP by half, but with carbamyl phosphate not at all; with CTP the inhibition was intermediate, one-fourth. By contrast, oligomycin inhibited Na+/Na+ exchange by one-fifth with all three substrates. A quantitative, steady-state kinetic model accounts for the relative magnitudes of Na+/K+ and Na+/Na+ exchanges with ATP, CTP, and carbamyl phosphate as substrates, as well as the extents of inhibition by oligomycin. The model requires that even when Na+ substitutes for K+ a slow step in the reaction sequence is the E2 to E1 conformational transition. PMID:2156564

Guerra, M; Robinson, J D; Steinberg, M

1990-03-30

379

Salicylic acid alleviates NaCl-induced changes in the metabolism of Matricaria chamomilla plants  

Microsoft Academic Search

Influence of 100 mM NaCl and 50 ?M salicylic acid (SA) and their combination on the metabolism of chamomile (Matricaria chamomilla) during 7 days was studied. NaCl reduced growth and selected physiological parameters and SA in combined treatment (NaCl + SA)\\u000a reversed majority of these symptoms. Application of SA reduced NaCl-induced increase of Na+ in the rosettes, but not in the roots. Accumulation of total

Jozef Ková?ik; Bo?ivoj Klejdus; Josef Hedbavny; Martin Ba?kor

2009-01-01

380

In Situ Observation of Dehydration-Induced Phase Transformation from Na2Nb2O6-H2O to NaNbO3  

E-print Network

In Situ Observation of Dehydration-Induced Phase Transformation from Na2Nb2O6-H2O to NaNbO3 Jong at high temperatures. After dehydration at 288 °C, the Na2Nb2O6-H2O becomes significantly destabilized

Wang, Zhong L.

381

Synthesis, photophysical properties, and photocatalytic applications of Bi doped NaTaO3 and Bi doped Na2Ta2O6 nanoparticles  

NASA Astrophysics Data System (ADS)

Phase formation and photophysical properties of bismuth doped sodium tantalum oxide (perovskite, defect pyrochlore) nanoparticles prepared by a hydrothermal method were studied in detail. It was revealed that the synthesis conditions like NaOH concentration and bismuth precursor (NaBiO3·2H2O) markedly affect the crystal structure of sodium tantalum oxide. At low NaOH concentration and high bismuth precursor (NaBiO3·2H2O) content, Bi doped Na2Ta2O6 (defect pyrochlore) phase was predominantly formed, while at higher NaOH concentration, Bi doped NaTaO3 (perovskite) phase was formed. It was observed that the defect pyrochlore (Bi doped Na2Ta2O6) phase was formed and stabilized by the presence of dopant precursor (NaBiO3·2H2O). The chemical analysis of the samples confirmed the doping of Bi3+ cations in both phases. Doping of bismuth enabled visible light absorption up to 500 nm in perovskite and defect pyrochlore type sodium tantalum oxide. Bi doped NaTaO3 samples showed better performance for the photocatalytic degradation of rhodamine B than that of Bi doped Na2Ta2O6, under visible light irritation (?>420 nm). The present results shed light on phase formation of sodium tantalate and these results are useful in understanding properties of NaTaO3 based compounds, synthesized by the hydrothermal method.

Kanhere, Pushkar; Tang, Yuxin; Zheng, Jianwei; Chen, Zhong

2013-12-01

382

ADP+orthophosphate (P(i)) stimulates an Na\\/K pump-mediated coefflux of P(i) and Na in human red blood cell ghosts  

Microsoft Academic Search

The Na\\/K pump in human red blood cells that normally exchanges 3 Nai for 2 Ko is known to continue to transport Na in a ouabain-sensitive and ATP-dependent manner when the medium is made free of both Nao and Ko. Although this Na efflux is called \\

R. Marin

1994-01-01

383

Pancreatic ?-cell Na+ channels control global Ca2+ signaling and oxidative metabolism by inducing Na+ and Ca2+ responses that are propagated into mitochondria.  

PubMed

Communication between the plasma membrane and mitochondria is essential for initiating the Ca(2+) and metabolic signals required for secretion in ? cells. Although voltage-dependent Na(+) channels are abundantly expressed in ? cells and activated by glucose, their role in communicating with mitochondria is unresolved. Here, we combined fluorescent Na(+), Ca(2+), and ATP imaging, electrophysiological analysis with tetrodotoxin (TTX)-dependent block of the Na(+) channel, and molecular manipulation of mitochondrial Ca(2+) transporters to study the communication between Na(+) channels and mitochondria. We show that TTX inhibits glucose-dependent depolarization and blocks cytosolic Na(+) and Ca(2+) responses and their propagation into mitochondria. TTX-sensitive mitochondrial Ca(2+) influx was largely blocked by knockdown of the mitochondrial Ca(2+) uniporter (MCU) expression. Knockdown of the mitochondrial Na(+)/Ca(2+) exchanger (NCLX) and Na(+) dose response analysis demonstrated that NCLX mediates the mitochondrial Na(+) influx and is tuned to sense the TTX-sensitive cytosolic Na(+) responses. Finally, TTX blocked glucose-dependent mitochondrial Ca(2+) rise, mitochondrial metabolic activity, and ATP production. Our results show that communication of the Na(+) channels with mitochondria shape both global Ca(2+) and metabolism signals linked to insulin secretion in ? cells.- Nita, I. I., Hershfinkel, M., Kantor, C., Rutter, G. A., Lewis, E. C., Sekler, I. Pancreatic ?-cell Na(+) channels control global Ca(2+) signaling and oxidative metabolism by inducing Na(+) and Ca(2+) responses that are propagated into mitochondria. PMID:24719357

Nita, Iulia I; Hershfinkel, Michal; Kantor, Chase; Rutter, Guy A; Lewis, Eli C; Sekler, Israel

2014-08-01

384

Ability of multicellular salt glands in Tamarix species to secrete Na+ and K+ selectively.  

PubMed

The present study aimed to determine the mechanism of cation-selective secretion by multicellular salt glands. Using a hydroponic culture system, the secretion and accumulation of Na(+) and K(+) in Tamarix ramosissima and T. laxa under different salt stresses (NaCl, KCl and NaCl+KCl) were studied. Additionally, the effects of salt gland inhibitors (orthovanadate, Ba(2+), ouabain, tetraethylammonium (TEA) and verapamil) on Na(+) and K(+) secretion and accumulation were examined. Treatment with NaCl (at 0-200 mmol L(-1) levels) significantly increased Na(+) secretion, whereas KCl treatment (at 0-200 mmol L(-1) levels) significantly increased K(+) secretion. The ratio of secretion to accumulation of Na(+) was higher than that of K(+). The changes in Na(+) and K(+) secretion differed after adding different ions into the single-salt solutions. Addition of NaCl to the KCl solution (at 100 mmol L(-1) level, respectively) led to a significant decrease in K(+) secretion rate, whereas addition of KCl to the NaCl solution (at 100 mmol L(-1) level, respectively) had little impact on the Na(+) secretion rate. These results indicated that Na+ secretion in Tamarix was highly selective. In addition, Na(+) secretion was significantly inhibited by orthovanadate, ouabain, TEA and verapamil, and K(+) secretion was significantly inhibited by ouabain, TEA and verapamil. The different impacts of orthovanadate on Na(+) and K(+) secretion might be the primary cause for the different Na(+) and K(+) secretion abilities of multicellular salt glands in Tamarix. PMID:21416329

Ma, Haiyan; Tian, Changyan; Feng, Gu; Yuan, Junfeng

2011-03-01

385

[La Medicina del Lavoro: 100 volumes].  

PubMed

With these pages La Medicina del Lavoro starts its 100th volume, so we have yet another historical occasion to celebrate the oldest occupational health journal in the world that is still publishing. Over the last few years we have had many occasions to celebrate, for example several anniversaries of the Journal (the 80th volume in 1989, 90 years in 1992, 100 years in 2001); the centenary of the foundation of the Clinica del Lavoro "Luigi Devoto" of Milan in 2001; the celebration of the 300 years' anniversary of the publication of De Morbis Artificum Diatriba by Bernardino Ramazzini, and we obviously hope to continue for many years to come in this positive outlook. One hundred volumes makes for a very large collection, with the highs and lows ofthe Journal's history (here we mean the variations in number of pages and physical size of the Journal). It is thanks to the Editors-in-chief(there have been very few so we can cite them all: Luigi Devoto, 1901-1936; Luigi Preti, 1936-1941; Enrico Vigliani, 1943-1992; e Vito Foà, 1992 to the present); the contributors who in various ways and with varying degrees of commitment but always with an exceptional personal participation, that it has been possible to reach 100 volumes, starting with C. Moreschi who, along with Luigi Devoto, was the first and sole editor at the Journal's foundation; up to the present extended and impressive editorial board; the printers (from the first. Tipografia Cooperativa, Via dei Molini in Pavia, to the latest: Casa Editrice Mattioli in Fidenza); the sponsors, including the most evident who, via advertising (rather limited as a matter offact), directly gave information about themselves, but also those who have often been or are behind the scenes, ensuring fundamental support which is not visible; content. articles, news, events, reports, ideas, opinions, photographs, tables, numbers... etc, which are really impossible to sum up. But the true collection which, for obvious reasons, cannot be individually named, consists of the people and the ideas that have enriched the history of the Journal in its over 100 years of existence. And the subscribers, above all, who by their almost anonymous presence have been the true guarantors of the Journal's ife. And of course the contributors who with their articles have consigned a part of their lives to history. Starting from 1925 we counted nearly 11.000, a really grand number. It would be wonderful if we could invite them all to a hypothetical (and impossible) grand convention to simply say "Thank you, your contributions will not be forgotten". There have been 100 volumes but in actual fact the Journal is more than 100 years old. It was founded in Pavia in 1901 as Il Lavoro-Rivista di fisiologia, clinica ed igiene del lavoro, and between 1901 and 1910 only three volumes were published, then, due to the difficulties during the First World War and the immediate post-war years, there were no issues in 1916, 1918 and 1919. Issues finally became regular in 1920 with volume 11; from that moment on not one issue was missed and the Journal even got through the Second World War without interruptions. In 1925, with volume 16, it took on the name that still distinguishes it to-day: La Medicina del Lavoro, "the official standard bearer of a work of enormous scientific, social and political content" as Luigi Devoto presented the event at the time. The first few years of the Journal were difficult ones (with only three volumes published in 10 years) to the effect that events such as the First International Congress on Occupational Diseases (Milano, 1906), the foundation of the International Commission for Occupational Health (1906), the First National Italian Congress on Occupational Diseases (Palermo, 1907), and above all the inauguration of the Clinica del Lavoro in Milano (20 March, 1910) are not reported in the Journal, which by 1911 had resumed publication but had moved to Milan. Many years have passed since those first three volumes and in the meantime we have moved on to another century and

Zocchetti, C

2009-01-01

386

Electron transfer and ionization in collisions of He-like ions with Na(3s) and Na(3p)  

NASA Astrophysics Data System (ADS)

Single electron transfer and ionization in collisions of He-like ions (N5+, O6+, Ne8+) and Na has been investigated both experimentally and theoretically at energies around the matching velocity of the valence electron (2 to 10 keV/amu). State selective cross sections and scattering angle distributions were obtained using recoil-ion momentum spectroscopy in combination with a magneto-optically cooled Na atom target. A strong dependence of the relative cross sections on the collision energy is observed. The results are compared with Classical-Trajectory Monte Carlo (CTMC) calculations and show an overall very good agreement.

Blank, I.; Otrantcr, S.; Meinema, C.; Olson, R. E.; Hoekstra, R.

2012-11-01

387

Elucidation of the Na+, K+-ATPase digitalis binding site.  

PubMed

Despite controversy over their use and the potential for toxic side effects, cardiac glycosides have remained an important clinical component for the treatment for congestive heart failure (CHF) and supraventricular arrhythmias since the effects of Digitalis purpurea were first described in 1785. While there is a wealth of information available with regard to the effects of these drugs on their pharmacological receptor, the Na(+), K(+)-ATPase, the exact molecular mechanism of digitalis binding and inhibition of the enzyme has remained elusive. In particular, the absence of structural knowledge about Na(+), K(+)-ATPase has thwarted the development of improved therapeutic agents with larger therapeutic indices via rational drug design approaches. Here, we propose a binding mode for digoxin and several analogues to the Na(+), K(+)-ATPase. A 3D-structural model of the extracellular loop regions of the catalytic alpha1-subunit of the digitalis-sensitive sheep Na(+), K(+)-ATPase was constructed from the crystal structure of an E(1)Ca(2+) conformation of the SERCA1a and a consensus orientation for digitalis binding was inferred from the in silico docking of a series of steroid-based cardiotonic compounds. Analyses of species-specific enzyme affinities for ouabain were also used to validate the model and, for the first time, propose a detailed model of the digitalis binding site. PMID:15886034

Keenan, Susan M; DeLisle, Robert K; Welsh, William J; Paula, Stefan; Ball, William J

2005-06-01

388

Optimization of Automated Float Glass Lines Byungsoo Na, Shabbir Ahmed  

E-print Network

Optimization of Automated Float Glass Lines Byungsoo Na, Shabbir Ahmed , George Nemhauser and Joel of Scope and Purpose Flat glass is approximately a $20 billion/year industry worldwide, with almost all flat glass products being manufactured on float glass lines. New technologies are allowing float glass

Ahmed, Shabbir

389

Stainless Steel NaK Circuit Integration and Fill Submission  

NASA Technical Reports Server (NTRS)

The Early Flight Fission Test Facilities (EFF-TF) team has been tasked by the Marshall Space Flight Center Nuclear Systems Office to design, fabricate, and test an actively pumped alkali metal flow circuit. The system, which was originally designed to hold a eutectic mixture of sodium potassium (NaK), was redesigned to hold lithium; but due to a shift in focus, it is once again being prepared for use with NaK. Changes made to the actively pumped, high temperature loop include the replacement of the expansion reservoir, addition of remotely operated valves, and modification of the support table. Basic circuit components include: reactor segment, NaK to gas heat exchanger, electromagnetic (EM) liquid metal pump, load/drain reservoir, expansion reservoir, instrumentation, and a spill reservoir. A 37-pin partial-array core (pin and flow path dimensions are the same as those in a full design) was selected for fabrication and test. This document summarizes the integration and fill of the pumped liquid metal NaK flow circuit.

Garber, Anne E.

2006-01-01

390

New Measurement of ?-? Angular Correlation in ^22Na  

NASA Astrophysics Data System (ADS)

We have measured the ?-? directional correlation in the hindered decay ^22 Na (3^+) arrow ^22Ne (2^+) using the Gammasphere array at LBNL. Our measurement contributes to determining a complete set of weak form factors for the ^22Na ? decay, testing corrections to allowed ? decay to second recoil order. The aim is to resolve a long-standing discrepancy between experiment and allowed-order theory in the electron capture to positron emission ratios. We used a 6 ?Ci source of ^22Na in the center of Gammasphere, a spherical array of 110 Ge detectors. The ?^+ is detected with a 3 mm thick plastic scintillator with 8% solid angle. The ?^+ decay is followed by a 1.275 MeV ? from the ^22Ne 2^+ state. We search for a directional dependence of the emitted ?'s detected in coincidence with a ? of form 1 + A\\cos^2 ?, with ? the angle between the ? and the individual Ge detectors, and A of order 10-3. Variable Ge detector efficiency is normalized by dividing coincident ? counts by single 1.275 MeV ?'s. Fitting the results versus ? - ? angle using gates on the ?^+ energy yields the energy-dependent A, which is sensitive to a linear combination of second-order form factors. Current data and analysis, and implications for ^22Na form factors will be presented.

Vetter, Paul; Bowers, Chris; Freedman, Stuart; Fujikawa, Brian; Reich, Jurgen; Shang, Song; Wasserman, Eric

1997-10-01

391

Free Energy for the Permeation of Na+ Ions and Their  

E-print Network

Free Energy for the Permeation of Na+ and Cl- Ions and Their Ion-Pair through a Zwitterionic-mail: ikhavru@mccammon.ucsd.edu Abstract: Understanding the mechanism of ion permeation across lipid bilayers for the ion permeation in disagreement with predictions from the simple electrostatic models. In this paper we

Lu, Benzhuo

392

High precision measurements of Na-26 beta(-) decay  

E-print Network

High-precision measurements of the half-life and beta-branching ratios for the beta(-) decay of Na-26 to Mg-26 have been measured in beta-counting and gamma-decay experiments, respectively. A 4 pi proportional counter and fast tape transport system...

Grinyer, GF; Svensson, CE; Andreoiu, C.; Andreyev, AN; Austin, RAE; Ball, GC; Chakrawarthy, RS; Finlay, P.; Garrett, PE; Hackman, G.; Hardy, John C.; Hyland, B.; Iacob, VE; Koopmans, KA; Kulp, WD; Leslie, JR; Macdonald, JA; Morton, AC; Ormand, WE; Osborne, CJ; Pearson, CJ; Phillips, AA; Sarazin, F.; Schumaker, MA; Scraggs, HC; Schwarzenberg, J.; Smith, MB; Valiente-Dobon, JJ; Waddington, JC; Wood, JL; Zganjar, EF.

2005-01-01

393

Transport of aromatic molecules in NaY zeolite powders  

SciTech Connect

This paper reports on Xenon-120 NMR that is used to probe macroscopic distributions of aromatic molecules adsorbed in a packed bed of 1-{mu}m NaY zeolite particles. Relative rates of guest transport through the intracrystalline (micro) and intercrystalline (macro) pores play a unique role in the axial distribution of sorbate molecules, such as hexamethylbenzene, in a zeolite powder. Xenon-129 NMR spectra show that a sharp HMB adsorption front advances through a bed of dehydrated NaY crystallites at 523 K. However, at 573 K or in the presence of coadsorbed water, HMB species disperse through the bed without forming a sharp boundary between adsorption zones. When guest transport is controlled by pseudosteady-state diffusion in the macropores, axial penetration of the bed by vapor-phase guest species occurs in a sharp adsorption front. A shrinking-core transport model then quantitatively estimates the intracrystalline diffusivities of HMB in dehydrated and partially hydrated NaY zeolite of 10{sup {minus}11} and 10{sup {minus}13} m{sup 2}/s, respectively, at 523 K. Xenon- 129 NMR proves to be a powerful tool for probing adsorbed guest distribution in zeolites, allowing relative time scales to be established for transport of molecular guests in NaY powders.

Chmelka, B.F.; Gillis, J.V.; Petersen, E.E.; Radke, C.J.

1990-10-01

394

FEORAGAN RUADH NA GAIDHEALTACHD Scottish Squirrel Group Update September 2011  

E-print Network

FEORAGAN RUADH NA GAIDHEALTACHD Scottish Squirrel Group Update September 2011 Strongholds Guidance is in production. Pilot sites are underway, Julia Garritt to update the meeting. Grey squirrel news No further records since Skye in December 2010. Plan to set up network of grey squirrel `panic bags' around

395

Grant Title: WALLACE FOUNDATION Funding Opportunity Number: N/A  

E-print Network

Education: Expanding arts learning opportunities for children and teens in school and beyond; (5) AudienceGrant Title: WALLACE FOUNDATION Funding Opportunity Number: N/A Agency/Department: The Wallace this approach strengthens the effectiveness of their funding. But it also means Wallace rarely funds unsolicited

Farritor, Shane

396

Grant Title: COOPER FOUNDATION Funding Opportunity Number: N/A  

E-print Network

of significant promise. Special funding priorites are given to: education, human services, arts, humanities its capital in support of people through education, human services, the arts, the humanitiesGrant Title: COOPER FOUNDATION Funding Opportunity Number: N/A Agency/Department: Cooper Foundation

Farritor, Shane

397

Benefiting from Polarization: Effects at High-NA Imaging  

E-print Network

157nm F2 Laser Mirror MirrorMirror Illuminator Mask Projection Lens Wafer Polarizer F2 Laser Mirror MirrorMirror Illuminator Mask Projection Lens Wafer Polarizer linearly polarized output beam unpolarizedBenefiting from Polarization: Effects at High-NA Imaging Bruce W. Smith L. Zavyalova, A. Estroff, Y

Zanibbi, Richard

398

National Aeronautics and Space Administration NaNotechNology Roadmap  

E-print Network

National Aeronautics and Space Administration · NaNotechNology Roadmap Technology Area 10 Michael A of fourteen technology area roadmaps, recommending the overall technology investment strategy in these areas, NASA plans updates to its integrated technology roadmap on a regular basis. #12;exeCuTive Summary

Waliser, Duane E.

399

Isolation of22Na for intense positron sources  

NASA Astrophysics Data System (ADS)

A method of removing22Na from Al via distillation is investigated. Distillation is rapid (?10 minutes) and nearly quantitative. When the distilled vapor is directed by a flow of He gas the deposit may be localized fairly well and easily recovered with water.

Griffin, H. C.; Steiger, T. D.; van House, J.; Skalsey, M.; Conti, R.; Rich, A.; Zitzewitz, P. W.

1989-03-01

400

Regulation of Intracellular Cholesterol Distribution by Na/K-ATPase*  

E-print Network

Regulation of Intracellular Cholesterol Distribution by Na/K-ATPase* Received for publication/K-ATPase 1 subunit produces a parallel decrease in both caveolin-1 and cholesterol in light fractions of LLC redistribution of cholesterol from the plasma membrane to intracellular compartments in the knockdown cells

Brand, Paul H.

401

Exploring Neutron-Rich Oxygen Isotopes with MoNA  

E-print Network

The Modular Neutron Array (MoNA) was used in conjunction with a large-gap dipole magnet (Sweeper) to measure neutron-unbound states in oxygen isotopes close to the neutron dripline. While no excited states were observed in 24O, a resonance at 45(2) keV above the neutron separation energy was observed in 23O.

N. Frank; T. Baumann; D. Bazin; J. Brown; P. A. DeYoung; J. E. Finck; A. Gade; J. Hinnefeld; R. Howes; J. -L. Lecouey; B. Luther; W. A. Peters; H. Scheit; A. Schiller; M. Thoennessen

2007-08-20

402

Optical Attenuation in MoNA and LISA Detector Elements  

NASA Astrophysics Data System (ADS)

The MoNA collaboration is a research group of students and faculty from 13 primarily undergraduate institutions, with detectors at the NSCL: MoNA (Modular Neutron Array) and the newly-built LISA (Large multi-Institutional Scintillating Array). These arrays each have 144 plastic scintillating bars. When a neutron collides with a hydrogen nucleus within the plastic, photomultiplier tubes at either end of the bar detect the scintillation photons. Their arrival times are used to determine the position of the event, but as the light travels through the detector it loses intensity exponentially. How dramatic this loss is can be described by a parameter called the attenuation length, with larger attenuation lengths corresponding to lower loss. Recently the MoNA collaboration conducted its LISA commissioning experiment investigating two-neutron decay states of ^25O. As a part of LISA's commissioning, we measured the attenuation lengths of the individual detector bars that make up the LISA array and compared these lengths with those of the older MoNA array. We found that the LISA bars had a larger attenuation length on average with impacts on detector efficiency and effective threshold.

Rice, Logan; Wong, Jonathan

2011-10-01

403

Grant Title: STARR FOUNDATION Funding Opportunity Number: N/A  

E-print Network

Grant Title: STARR FOUNDATION Funding Opportunity Number: N/A Agency/Department: Starr Foundation: The Foundation funds organizations that provide need-based financial aid to students seeking to attend secondary. The Foundation makes significant grants to large cultural institutions, smaller arts organizations, community

Farritor, Shane

404

Synthesis of Na-zeolites from fly ash  

Microsoft Academic Search

The present study focuses on the synthesis of zeolites after fly ash activation, the major objectives being: (a) to study the activation processes; (b) to elucidate the activation conditions for maximum synthesis efficiency; (c) to optimize the conditions for the monomineral synthesis; and (d) to test synthesis efficiencies for different fly ash types. Fly ash was activated by NaOH and

Xavier Querol; Felicià Plana; Andrés Alastuey; Angel López-Soler

1997-01-01

405

A Lepton Universality Test at CERN NA62 Experiment  

E-print Network

The NA62 experiment at CERN collected a large sample of K+ --> enu decays during a dedicated run in 2007, aiming at a precise test of lepton universality by measurement of the helicity suppressed ratio RK = BR(K+ --> enu)/BR(K+ --> munu). A preliminary result of the analysis of a partial data sample of 51089 K+ --> enu candidates is presented.

Evgueni Goudzovski

2010-05-07

406

POWER FROM NA COOLED REACTOR REACTOR DESIGN AND FEASIBILITY PROBLEM  

Microsoft Academic Search

Work done on the study of a Na cooled, graphite moderated nuclear ; reactor for power production is summarized. The preliminary design calculations ; and results are described for a heterogeneous, thermal reactor using rod type ; fuel elements of slightly enriched U. The total heat capacity is 300,000 kw with ; a nominal electric power producing capacity of 75,000

D. R. Bennion; R. L. Hickmott; N. A. Krohn; W. J. McCarthy; R. A. Moore; H. J. Stumpf; L. A. Waldman

1952-01-01

407

Monitorização eletroencefalográfica ambulatorial na epilepsia de difícil controle da infância  

Microsoft Academic Search

RESUMO - O objetivo deste estudo foi analisar através da monitorização eletroencefalográfica ambulatorial contínua e prolongada a distribuição temporal de descargas paroxísticas em sono e em vigília de crianças e adolescentes com epilepsia de difícil controle medicamentoso. Foram selecionadas 21 pacientes na faixa etária de 4 a 17 anos de idade com epilepsia de difícil controle medicamentoso, sendo 52,3 %

Sueli Rizzutti; Mauro Muszkat; Carlos José Reis de Campos

2001-01-01

408

Adolescência e violência: a psicanálise na prática social  

Microsoft Academic Search

Este projeto foi iniciado em 1994, culminando em 97 com a publicação do livro Adolescência e Violência: Conseqüências da Rea- lidade Brasileira (Levisky,1997a). Damos continuidade a esta iniciativa, abordando o binômio ado- lescência e violência a partir da apreensão psicanalítica destes fenôme- nos e seus desdobramentos na prática social. São trabalhos oriundos da experiência clínica de psicanalistas, em sua maioria,

David Léo Levisky

409

Altered erythrocyte Na-K pump in anorectic patients  

SciTech Connect

The status of the erythrocyte sodium pump was evaluated in a group of patients suffering from anorexia nervosa and a group of healthy female control subjects. Anorectic patients showed significantly higher mean values of digoxin-binding sites/cell (ie, the number of Na-K-ATPase units) with respect to control subjects while no differences were found in the specific /sup 86/Rb uptake (which reflects the Na-K-ATPase activity) between the two groups. A significant correlation was found between relative weight and the number of Na-K-ATPase pump units (r = -0.66; P less than 0.0001). Anorectic patients showed lower serum T3 concentrations (71.3 +/- 53 ng/dL) with respect to control subjects (100.8 +/- 4.7 ng/dL; P less than 0.0005) and a significant negative correlation between T3 levels and the number of pump units (r = -0.52; P less than 0.003) was found. This study therefore shows that the erythrocyte Na-K pump may be altered in several anorectic patients. The authors suggest that this feature could be interrelated with the degree of underweight and/or malnutrition.

Pasquali, R.; Strocchi, E.; Malini, P.; Casimirri, F.; Ambrosioni, E.; Melchionda, N.; Labo, G.

1985-07-01

410

Global structure of small Na clusters in different approaches  

Microsoft Academic Search

We compare the shapes of small Na clusters as they result from the jellium model, the cylindrically averaged pseudopotential scheme, and the distance-dependent tight-binding approach. Although these are three distinctively different approaches, we find a good agreement amongst the results, showing that all three models, taken in their appropriate domain of descriptive power, give an equally reliable picture of metal

F. Spiegelmann; R. Poteau; B. Montag; P.-G. Reinhard

1998-01-01

411

Purification of the cardiac Na+-Ca2+ exchange protein.  

PubMed

We have used fractionation procedures to enrich solubilized cardiac sarcolemma in the Na+-Ca2+ exchange protein. Sarcolemma is extracted with an alkaline medium to remove peripheral proteins and is then solubilized with decylmaltoside. Next, the exchanger is applied to DEAE-Sepharose and eluted with high salt. The DEAE fraction is applied to WGA-agarose, and a small fraction of protein, enriched in the exchanger, can be eluted by changing the detergent to Triton X-100. This fraction is reconstituted into asolectin proteoliposomes for measurement of Na+-Ca2+ exchange activity and gel electrophoresis. The purified fraction has a Na+-Ca2+ exchange activity of 600 nmol Ca2+/mg of protein per s at 10 microM Ca2+ and a purification factor of about 30 as compared with control reconstituted sarcolemmal vesicles. Ca2+-Ca2+ exchange and Na+-Ca2+ exchange activities were both present in the same final reconstituted vesicles indicating that the same protein is responsible for both transport activities. SDS-PAGE reveals two prominent protein bands at 70 and 120 kDa. After mild chymotrypsin treatment (1 microgram/ml), there is no loss of exchange activity, but the 120 kDa band disappears and the 70 kDa band becomes more dense. This suggests that the 70 kDa band is due to an active proteolytic fragment of the 120 kDa protein. Under non-reducing gel conditions, only a single protein band is seen with an apparent molecular weight of 160 kDa. Antibodies to the purified exchanger preparation are able to immunoprecipitate exchange activity and confirm that the 70 kDa protein derives from the 120 kDa protein. We propose that both the 70 and 120 kDa proteins are associated with the Na+-Ca2+ exchanger. PMID:3191125

Philipson, K D; Longoni, S; Ward, R

1988-11-22

412

Surface color centers on NaCl(001)  

NASA Astrophysics Data System (ADS)

Charging effects and probe induced damage usually render impossible the investigation of ionic crystal surfaces by means of many of the conventional surface science tools, like e.g. low-energy electron diffraction (LEED). A way out of this dilemma is using low current densities on surfaces of thin epitaxial insulator films grown on a conducting substrate. We studied the creation of color centers in and on epitaxial NaCl on Ge(001) by means of ELS-LEED, a unique combination of high resolution LEED and energy loss spectroscopy (ELS). Surface color centers determine the chemical reactivity of the NaCl(001) surface as will be demonstrated for the adsorption of water. - Different kinetics of formation permit the identification of different types of surface color centers. At temperatures below 200 K prolonged low-energy electron bombardment creates predominantly surface F- and M-centers appearing as randomly distributed static point defects. Only at room temperature does diffusion lead to the formation of Na clusters and colloids. When water is present anion vacancies are transformed into OH^--centers. During the formation of the two-dimensional condensed phase of H_2O on NaCl(001), OH^--centers act as nucleation centers for H_2O clusters. These limit the long-range order of the 2D-phase, reducing the superstructure from a c(2x12) symmetry as formed on annealed NaCl films to c(2x4). As a model we present an ice-like bilayer with a vertical modulation.

Zielasek, V.; Hildebrandt, T.; Henzler, M.

1998-03-01

413

Stoichiometric Relationship between Na+ Ions Transported and Glucose Consumed in Human Erythrocytes: Bayesian Analysis of 23Na and 13C NMR Time Course Data  

PubMed Central

We examined the response of Na+,K+-ATPase (NKA) to monensin, a Na+ ionophore, with and without ouabain, an NKA inhibitor, in suspensions of human erythrocytes (red blood cells). A combination of 13C and 23Na NMR methods allowed the recording of intra- and extracellular Na+, and 13C-labeled glucose time courses. The net influx of Na+ and the consumption of glucose were measured with and without NKA inhibited by ouabain. A Bayesian analysis was used to determine probability distributions of the parameter values of a minimalist mathematical model of the kinetics involved, and then used to infer the rates of Na+ transported and glucose consumed. It was estimated that the numerical relationship between the number of Na+ ions transported by NKA per molecule of glucose consumed by a red blood cell was close to the ratio 6.0:1.0, agreeing with theoretical prediction. PMID:23601315

Puckeridge, Max; Chapman, Bogdan E.; Conigrave, Arthur D.; Grieve, Stuart M.; Figtree, Gemma A.; Kuchel, Philip W.

2013-01-01

414

Stoichiometric relationship between Na(+) ions transported and glucose consumed in human erythrocytes: Bayesian analysis of (23)Na and (13)C NMR time course data.  

PubMed

We examined the response of Na(+),K(+)-ATPase (NKA) to monensin, a Na(+) ionophore, with and without ouabain, an NKA inhibitor, in suspensions of human erythrocytes (red blood cells). A combination of (13)C and (23)Na NMR methods allowed the recording of intra- and extracellular Na(+), and (13)C-labeled glucose time courses. The net influx of Na(+) and the consumption of glucose were measured with and without NKA inhibited by ouabain. A Bayesian analysis was used to determine probability distributions of the parameter values of a minimalist mathematical model of the kinetics involved, and then used to infer the rates of Na(+) transported and glucose consumed. It was estimated that the numerical relationship between the number of Na(+) ions transported by NKA per molecule of glucose consumed by a red blood cell was close to the ratio 6.0:1.0, agreeing with theoretical prediction. PMID:23601315

Puckeridge, Max; Chapman, Bogdan E; Conigrave, Arthur D; Grieve, Stuart M; Figtree, Gemma A; Kuchel, Philip W

2013-04-16

415

Synthesis of Li (x)Na (2-x)Mn 2S 3 and LiNaMnS 2 through redox-induced ion exchange reactions  

NASA Astrophysics Data System (ADS)

Na 2Mn 2S 3 was oxidatively deintercalated using iodine in acetonitrile to yield Na 1.3Mn 2S 3, with lattice constants nearly identical to that of the reactant. Lithium was then reductively intercalated into the oxidized product to yield Li 0.7Na 1.3Mn 2S 3. When heated, this metastable compound decomposed to form a new crystalline compound, LiNaMnS 2, along with MnS and residual Na 2Mn 2S 3. Single crystal X-ray diffraction structural analysis of LiNaMnS 2 revealed that this compound crystallizes in P-3 m1 with cell parameters a=4.0479(6) Å, c=6.7759(14) Å, V=96.15(3) Å 3 ( Z=1, w R2=0.0367) in the NaLiCdS 2 structure-type.

Luthy, Joshua A.; Goodman, Phillip L.; Martin, Benjamin R.

2009-03-01

416

Two novel Zintl compounds Na 12Ge 8Sn and Na 15Ge 8SnP: Single crystal and electronic structures  

NASA Astrophysics Data System (ADS)

Two mixed anionic Zintl phases, Na 12Ge 8Sn and Na 15Ge 8SnP, have been synthesized and structurally characterized. Na 12Ge 8Sn crystallizes in the tetragonal space group P4 12 12 (#92, a = 14.1172(2) Å, c = 21.8483(7) Å, V = 4354.3(2) Å 3, Z = 8, and R/ wR = 0.0481/0.1213) and Na 15Ge 8SnP crystallizes in the orthorhombic space group Cmcm (#63, a = 17.517(4) Å, b = 12.890(3) Å, c = 11.111(2) Å, V = 2508.7(9) Å 3, Z = 4, and R/ wR = 0.0313/0.0669). Both compounds adopt new structure types and are made up of isolated Na + cations, anionic (Ge 4) 4- tetrahedral clusters, and Sn 4- or P 3- anions. The structure of Na 12Ge 8Sn can be described as a square packing of two kinds of columns, highly distorted Sn centered Na icosahedra chains ([NaSn]5+?1) and highly distorted Na(1) centered anti-rectangular prism (four (Ge 4) 4- and four Na, [Na()2]5-?1) chains. The structure of Na 15Ge 8SnP is composed of cationic [NaSnP]8+?1 saw tooth-like chains, which are made up of Sn centered Na bicapped hexagonal prisms and P centered tricapped trigonal prisms, extending along the c axis with anionic (Ge 4) 4- tetrahedral clusters between the chains. The electronic structures have been studied using density functional theory.

Dong, Yongkwan; Ranjan, Chinmoy; DiSalvo, Francis J.

2008-05-01

417

Na-O Anticorrelation and Horizontal Branches. V. The Na-O anticorrelation in NGC 6441 from Giraffe spectra  

E-print Network

We present an analysis of FLAMES-Giraffe spectra for several bright giants in NGC 6441, to investigate the presence and extent of the Na-O anticorrelation in this anomalous globular cluster. The field of NGC 6441 is very crowded, with severe contamination by foreground (mainly bulge) field stars. Appropriate membership criteria were devised to identify a group of 25 likely cluster members among the about 130 stars observed. Combined with the UVES data obtained with the same observations, high dispersion abundance analyses are now available for a total of 30 stars in NGC 6441, 29 of them having data for both O and Na. The spectra were analyzed by a standard line analysis procedure; care was taken to minimize the impact of the differential interstellar reddening throughout the cluster, and to extract reliable information from crowded, and moderately high S/N (30-70), moderately high resolution (R ~ 23,000) spectra. NGC 6441 is very metal-rich ([Fe/H]=$-0.34\\pm 0.02\\pm0.04$ dex). There is no clear sign of star-to-star scatter in the Fe-peak elements. The alpha-elements Mg, Si, Ca, and Ti are overabundant by rather large factors, suggesting that the cluster formed from material enriched by massive core collapse SNe. The O-Na anticorrelation is well defined, with about 1/4 of the stars being Na-rich and O-poor. One of the stars is a Ba-rich and moderately C-rich star. The distribution of [Na/O] ratios among RGB stars in NGC 6441 appears similar to the distribution of colors of stars along the horizontal branch. The fraction of Na-poor, O-rich stars found in NGC 6441 agrees well with that of stars on the red horizontal branch of this cluster (in both cases about 80%), with a sloping distribution toward lower values of [O/Na] (among RGB stars and bluer colors (among HB stars).

R. G. Gratton; S. Lucatello; A. Bragaglia; E. Carretta; S. Cassisi; Y. Momany; E. Pancino; E. Valenti; V. Caloi; R. Claudi; F. D'Antona; S. Desidera; P. Fran{ç}ois; G. James; S. Moehler; S. Ortolani; L. Pasquini; G. Piotto; A. Recio-Blanco

2007-01-08

418

Na-O anticorrelation and horizontal branches. V. The Na-O anticorrelation in NGC 6441 from Giraffe spectra  

NASA Astrophysics Data System (ADS)

Aims:We present an analysis of FLAMES-Giraffe spectra for several bright giants in NGC 6441, to investigate the presence and extent of the Na-O anticorrelation in this anomalous globular cluster. Methods: The field of NGC 6441 is very crowded, with severe contamination by foreground (mainly bulge) field stars. Appropriate membership criteria were devised to identify a group of 25 likely cluster members among the about 130 stars observed. Combined with the UVES data obtained with the same observations (Gratton et al. 2006), high dispersion abundance analyses are now available for a total of 30 stars in NGC 6441, 29 of them having data for both O and Na. The spectra were analyzed by a standard line analysis procedure; care was taken to minimize the impact of the differential interstellar reddening throughout the cluster, and to extract reliable information from crowded, and moderately high S/N (30-70), moderately high resolution (R˜ 23 000) spectra. Results: NGC 6441 has the typical abundance pattern seen in several other globular clusters. It is very metal-rich ([Fe/H] = -0.34 ± 0.02 ± 0.04 dex). There is no clear sign of star-to-star scatter in the Fe-peak elements. The ?-elements Mg, Si, Ca, and Ti are overabundant by rather large factors, suggesting that the cluster formed from material enriched by massive core collapse SNe. The O-Na anticorrelation is well defined, with about 1/4 of the stars being Na-rich and O-poor. One of the stars is a Ba-rich and moderately C-rich star. Such stars are rare in globular clusters. Conclusions: .The distribution of [Na/O] ratios among RGB stars in NGC 6441 appears similar to the distribution of colors of stars along the horizontal branch. The fraction of Na-poor, O-rich stars found in NGC 6441 agrees well with that of stars on the red horizontal branch of this cluster (in both cases about 80%), with a sloping distribution toward lower values of [O/Na] (among RGB stars) and bluer colors (among HB stars). Based on data collected at the European Southern Observatory with the VLT-UT2, Paranal, Chile (ESO Program 073.D-0211). Full Table [see full text] is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/464/953

Gratton, R. G.; Lucatello, S.; Bragaglia, A.; Carretta, E.; Cassisi, S.; Momany, Y.; Pancino, E.; Valenti, E.; Caloi, V.; Claudi, R.; D'Antona, F.; Desidera, S.; François, P.; James, G.; Moehler, S.; Ortolani, S.; Pasquini, L.; Piotto, G.; Recio-Blanco, A.

2007-03-01

419

Los discursos del miedo en la prensa uruguaya  

Microsoft Academic Search

A fines de julio de 2002 el Uruguay sufre una de sus peores crisis financieras, económicas y sociales. Reprogramaciones de las cuentas bancarias, tanto de instituciones privadas como del Estado, supuestos saqueos por \\

María Ángela Giaimo

420

La Revolucin del Shale Gas Profesor: Hugh Rudnick  

E-print Network

La Revolución del Shale Gas Mayo 2011 Profesor: Hugh Rudnick Profesional Externo: Verónica Cortés........................................................................................................................................ 6 ¿Qué es el Shale Gas...................................................................................................................................... 7 Shale Gas

Rudnick, Hugh

421

Servei d'Activitats Culturals Normativa interna del SAC  

E-print Network

Servei d'Activitats Culturals Normativa interna del SAC Formaci� 1. Lloc, dates i horaris Els� altres criteris, si ho considera oport�. 5. Anul�laci� d'un curs El SAC es reserva la possibilitat de

Oro, Daniel

422

Living Legacy: A Conversation with Carolina Gomez del Valle.  

ERIC Educational Resources Information Center

Carolina Gomez del Valle has been involved in training other Montessorians in Mexico, Chile, Nicaragua, Peru, and Taiwan. This interview explores her experiences with Montessori education and describes how she has woven her religious training and Montessori philosophy together. (PAM)

Montessori Life, 1993

1993-01-01

423

ESTRUCTURAS ALGEBRAICAS Nombre del profesor: Jos F. Fernando Galvn  

E-print Network

ESTRUCTURAS ALGEBRAICAS Grupos A Nombre del profesor: Jos� F. Fernando Galv�n Tutor�as: ser�n en el estructura. Factores invariantes y divisores elementales. El grupo de las unidades de un cuerpo finito

Fernando, Jose F.

424

ARTICLEINPRESS Seismic stratigraphy of Lago Fagnano sediments (Tierra del Fuego,  

E-print Network

S in the heart of the Island of Tierra del Fuego, Lago Fagnano occupies the deepest of a chain of en strong tectonic pulses along the MFT system. Gravity cores show a regular alternation of light and dark

Gilli, Adrian

425

FRAGOMEN, DEL REY, BERNSEN & LOEWY, LLP US IMMIGRATION CLIENT ALERT  

E-print Network

FRAGOMEN, DEL REY, BERNSEN & LOEWY, LLP US IMMIGRATION CLIENT ALERT If you have any questions about to the United States. This Client Alert provides general guidance on procedures, including visa issuance at U

Scharer, John E.

426

Energetics of phosphate frameworks containing zinc and cobalt: NaZnPO 4, NaH(ZnPO 4) 2, NaZnPO 4·H 2O, NaZnPO 4· {4}/{3}H 2O, and NaCo xZn 1-xPO 4· {4}/{3}H 2O  

NASA Astrophysics Data System (ADS)

Differential scanning calorimetry and high temperature oxide melt solution calorimetry were used to study the enthalpy of the ?- ? phase transformation of NaZnPO 4 and enthalpies of formation of ?-NaZnPO 4, NaH(ZnPO 4) 2, NaZnPO 4·H 2O, and NaCo xZn 1-xPO 4· {4}/{3}H 2O ( x=0, 0.1, 0.2, 0.3). The enthalpies of formation from the oxides of cobalt substituted in NaZnPO 4· {4}/{3}H 2O do not depend on cobalt content, confirming similar acid-base interactions for Zn-PO 4 and Co-PO 4. While water molecules stabilize zinc phosphate frameworks through solvating a cation or forming extra hydrogen bonds, the partial substitution of water for sodium oxide to form NaH(ZnPO 4) 2 represents the formation of an acidic compound with weaker acid-base interactions and less exothermic enthalpy of formation from oxides than Na 2(ZnPO 4) 2.

Le, So-Nhu; Navrotsky, Alexandra

2007-09-01

427

Quantum mechanical calculation of 23 Na NMR shieldings in silicates and aluminosilicates  

Microsoft Academic Search

To assist in the assignment and interpretation of 23Na NMR spectra in silicate and aluminosilicate minerals and glasses we have calculated the 23Na NMR shieldings and the electric field gradients (EFG) at the Na for a number of Na-containing species. Included are Na(OH2)\\u000a n\\u000a \\u000a +, n?=?1, 2, 4, 5, 6 and 8, and Na+ complexes with SiH3OH, SiH3ONa and O(SiH3)2.

J. A. Tossell

1999-01-01

428

INTEX-NA: Intercontinental Chemical Transport Experiment - North America  

NASA Technical Reports Server (NTRS)

INTEX-NA is an integrated atmospheric chemistry field experiment to be performed over North America using the NASA DC-8 and P-3B aircraft as its primary platforms. It seeks to understand the exchange of chemicals and aerosols between continents and the global troposphere. The constituents of interest are ozone and its precursors (hydrocarbons, NOX and HOX), aerosols, and the major greenhouse gases (CO2, CH4, N2O). INTEX-NA will provide the observational database needed to quantify inflow, outflow, and transformations of chemicals over North America. INTEX-NA is to be performed in two phases. Phase A will take place during the period of May-August 2004 and Phase B during March-June 2006. Phase A is in summer when photochemistry is most intense and climatic issues involving aerosols and carbon cycle are most pressing, and Phase B is in spring when Asian transport to North America is at its peak. INTEX-NA will coordinate its activities with concurrent measurement programs including satellites (e. g. Terra, Aura, Envisat), field activities undertaken by the North American Carbon Program (NACP), and other U.S. and international partners. However, it is being designed as a 'stand alone' mission such that its successful execution is not contingent on other programs. Synthesis of the ensemble of observation from surface, airborne, and space platforms, with the help of global/regional models is an important It is anticipated that approximately 175 flight hours for each of the aircraft (DC-8 and P-3B) will be required for each Phase. Principal operational sites are tentatively selected to be Bangor, ME; Wallops Island, VA; Seattle, WA; Rhinelander, WI; Lancaster, CA; and New Orleans, LA. These coastal and continental sites can support large missions and are suitable for INTEX-NA objectives. The experiment will be supported by forecasts from meteorological and chemical models, satellite observations, surface networks, and enhanced O3,-sonde releases. In addition to characterizing Atlantic-outflow and Pacific-inflow, INTEX-NA will characterize air masses transported between the U.S., Canada, and Mexico. INTEX-NA will be the first continental scale inflow, outflow, and transformation experiment to be performed over North America. It will provide the most comprehensive observational data set to date to understand the O3/NOX/HOX/aerosol photochemical system and the carbon cycle. One of the critical needs of the carbon cycle research is to obtain large-scale vertical and horizontal concentration gradients of CO2, throughout the troposphere over continental source/sink regions. INTEX-NA is ideally suited to perform this role. Coastal and continental operational sites will allow us to develop a curtain profile of greenhouse gases (e. g. CO2,) and other key pollutants across North America. Such information is central to our quantitative understanding of chemical budgets on the continental scale. We expect to provide a number of satellite under-flights over land and water to test and validate observations from the appropriate satellite platform (e. g. Aura). We plan to develop strong collaborations with other national and international observational programs. Results from INTEX-NA should directly benefit the development of environmental policy for air quality and climate change.

Singh, Hanwant B.; Jacob, D.; Pfister, L.; Hipskind, R. Stephen (Technical Monitor)

2002-01-01

429

El metabolismo social del País Vasco desde el análisis de flujos materiales  

Microsoft Academic Search

La desvinculación de la mejora del bienestar respecto del uso de los recursos y de la contaminación es esencial para lograr un desarrollo sostenible. Para avanzar en esta dirección es preciso partir del conocimiento del metabolismo de la sociedad. Es decir, debemos analizar en qué medida nuestras sociedades “ingieren” materias primas, que son “metabolizadas” para producir bienes y servicios, y

Iñaki Arto

2009-01-01

430

Comunicacionas mansualas dal Instituto Intllrnacional de la Potase, Berna (Suiza) Ciencia del Suelo  

E-print Network

del Suelo 728 continuacion N° 5/1981 La quimica del potasio en suelos arenosos* (On the chemistry of potassium in sandy soils) D, L. Sparks Profesor Auxiliar de Qulmica Fisica del Suelo, Departamento de y nativo en suelos Dothan. Sparks D.L., Zelazny L. W., Martens D. C.: Cineticas del Intercambio de

Sparks, Donald L.

431

Lecciones del programa de prevención temprana de la violencia, Medellín, Colombia  

Microsoft Academic Search

Se describen las características y evolución del Programa de Prevención Temprana de la Agresión del Municipio de Medellin, Colombia, que, al parecer, es la más amplia experiencia de su género en Latinoamérica. Se realiza la primera evaluación del impacto atribuible a este programa, focalizada en su etapa inicial. El análisis antes \\/ después reporta varios efectos positivos del Programa. Conclusión

Luis Fernando Duque; José Fernando Orduz; Juan de Jesús Sandoval; Beatriz Elena Caicedo; Joanne Klevens

2007-01-01

432

PUEDE EXPLICARSE EL PRECIO EXTERNO DEL CAFÉ CON UN MODELO ECONOMETRICO NO LINEAL?  

Microsoft Academic Search

El precio internacional del café, como el de la mayoría de los productos primarios se ha caracterizado por la inestabilidad y las grandes fluctuaciones. La formación del precio del café verde es un proceso complejo que depende de una multiplicidad de variables, como la calidad y disponibilidad del producto, el lugar de origen, el sitio de compra, las expectativas de

Franz Alonso Hamann S

1996-01-01

433

Gli approcci terapeutici al trattamento del dolore cronico  

Microsoft Academic Search

\\u000a La terapia del paziente con dolore cronico inizia molto prima dell’incontro con il clinico, poiché tutto ciò che ha preceduto\\u000a il primo appuntamento, in un lasso di tempo talvolta molto lungo, ha portato il paziente a una parziale presa di coscienza\\u000a ed elaborazione del proprio disagio (Ercolani 1997). Presentandosi dal clinico, il paziente tende il più delle volte a sottovalutare

Gianluca Castelnuovo; Mauro Ercolani; Mario Tavola; Daniele Rovaris; Lara Bellardita; Paola Cuzziol; Enrico Molinari

434

Aportació a coneixement florístic del Moianès (Catalunya central)  

Microsoft Academic Search

Seguint en la línia d'ampliació del coneixement florístic de l'àrea del Moianès, presentem dades d'interès corològic de 46 tàxons. Es tracta bàsicament d'espècies d'ambients forestals i pradencs, bona part no citades d'aquest sector i algunes de molt rares o inexistents al territori ausosegàrric. Hi ha un primer grup d'espècies, que a les terres catalanes són bàsicament pirinenques [Linum viscosum L.,

Arnau Mercadé López

2007-01-01

435

Student Competition: Siting Potential Dams at Camp Del Webb, Utah  

E-print Network

Siting Potential Dams at Camp Del Webb, Utah Presented By: Kyle Wamser Problem ? Camp Del Webb is Lacking an Onsite Lake ? High Adventure Bases generally need aquatics ? Large lake nearby, but transportation is required ? Possible Solution... hillshade ? Finding Possible Lake Locations ? Added three potential dam sites ? Calculated watersheds ? Extended dams through terrain to prevent runoff on the sides ? Calculated watershed dam elevation, which identified lakes Results...

Wamser, William Kyle

2007-11-14

436

Stabilization of Na,K-ATPase by ionic interactions.  

PubMed

The effect of ions on the thermostability and unfolding of Na,K-ATPase from shark salt gland was studied and compared with that of Na,K-ATPase from pig kidney by using differential scanning calorimetry (DSC) and activity assays. In 1 mM histidine at pH 7, the shark enzyme inactivates rapidly at 20 degrees C, as does the kidney enzyme at 42 degrees C (but not at 20 degrees C). Increasing ionic strength by addition of 20 mM histidine, or of 1 mM NaCl or KCl, protects both enzymes against this rapid inactivation. As detected by DSC, the shark enzyme undergoes thermal unfolding at lower temperature (Tm approximately 45 degrees C) than does the kidney enzyme (Tm approximately 55 degrees C). Both calorimetric endotherms indicate multi-step unfolding, probably associated with different cooperative domains. Whereas the overall heat of unfolding is similar for the kidney enzyme in either 1 mM or 20 mM histidine, components with high mid-point temperatures are lost from the unfolding transition of the shark enzyme in 1 mM histidine, relative to that in 20 mM histidine. This is attributed to partial unfolding of the enzyme due to a high hydrostatic pressure during centrifugation of DSC samples at low ionic strength, which correlates with inactivation measurements. Addition of 10 mM NaCl to shark enzyme in 1 mM histidine protects against inactivation during centrifugation of the DSC sample, but incubation for 1 h at 20 degrees C prior to addition of NaCl results in loss of components with lower mid-point temperatures within the unfolding transition. Cations at millimolar concentration therefore afford at least two distinct modes of stabilization, likely affecting separate cooperative domains. The different thermal stabilities and denaturation temperatures of the two Na,K-ATPases correlate with the respective physiological temperatures, and may be attributed to the different lipid environments. PMID:18187035

Fodor, Elfrieda; Fedosova, Natalya U; Ferencz, Csilla; Marsh, Derek; Pali, Tibor; Esmann, Mikael

2008-04-01

437

Difusión de resultados iniciales del Estudio del Tamoxifeno y del Raloxifeno (STAR): el fármaco para el tratamiento de la osteoporosis, raloxifeno, es tan efectivo como el Tamoxifeno en la prevención de cáncer de seno invasor  

Cancer.gov

Los resultados iniciales del Estudio del Tamoxifeno y del Raloxifeno, STAR, demuestran que el fármaco raloxifeno, actualmente utilizado para prevenir y tratar la osteoporosis en mujeres posmenopáusicas, funciona tan bien como el tamoxifeno para reducir el riesgo de cáncer de seno entre las mujeres posmenopáusicas que tienen riesgo elevado de padecer la enfermedad. Preguntas y respuestas

438

[Effect of NaHCO3 stress on uptake and transportation of Na+, K+ and Ca2+ in three shrub species].  

PubMed

We detected absorption and transportation of ions in the leaves of Atriplex nummularia, Atriplex canescens and Lycium barbarum under NaHCO3 stress (300 mmol x L(-1)) by using atomic absorption spectrophotometry and non-invasive ion flux measurement. The results showed that leaves of the A. nummularia, A. canescens and L. barbarum exhibited a high capacity to induce the Na+ accumulation when compared with that of control. The higher the concentration of NaHCO3 treatment, the more Na+ accumulated in the leaves of the three plants under experimental condition. L. barbarum showed a higher Na+ efflux in the mesophyll cells, whereas A. nummularia and A. canescens showed a relative lower efflux. A lower K+ content and a higher Na+/K+ ratio were detected in leaves of A. nummularia and L. barbarum. However, a higher K+ content and a lower Na+/K+ ratio were seen in leaves of A. canescens. Due to induction of Ca2+ efflux under the NaHCO3 treatment, a lower Ca2+ content and a higher Na+/Ca2+ ratio were observed in L. barbarum. On the contrary, a higher Ca2+ influx was observed in A. nummularia and A. canescens. These results suggested that the three shrubs species had different Na+ segmentation strategies. The accumulation of Na+ inhibited Ca2+ absorption in leaves of L. barbarum, while in the A. nummularia and A. canescens, Ca2+ influx induced [Ca2+]cyt which preserved a less-depolarized PM and then inhibited K efflux. The maintaining of cellular K+/Na+ homeostasis in A. nummularia and A. canescens might be achieved by the induction of [Ca2+]cyt under the NaHCO3 treatment. PMID:24984488

Mao, Gui-Lian; Li, Guo-Qi; Xu, Xing; Zhang, Xin-Xue

2014-03-01

439

Cirug?a de los trastornos del comportamiento: el estado del arte  

PubMed Central

Introducción: La cirugía de los trastornos del comportamiento (CTC) se está convirtiendo en un tratamiento más común desde el desarrollo de la neuromodulación. Métodos: Este artículo es una revisión no sistemática de la historia, indicaciones actuales, técnicas y blancos quirúrgicos de la CTC. Dividimos su historia en 3 eras: la primera comienza en los inicios de la psicocirugía y termina con el desarrollo de las tícnicas estereotácticas, cuando comienza la segunda era. Ésta se caracteriza por la realización de lesiones estereotácticas. Nos encontramos transitando la tercera era, que comienza cuando la estimulación cerebral profunda (ECP) comienza a ser usada en CTC. Resultados: A pesar de los errores graves cometidos en el pasado, hoy en día, la CTC está renaciendo. Los trastornos psiquiátricos que se más frecuentemente se tratan con cirugía son: depresión refractaria, trastorno obsesivo-compulsivo y síndrome de Tourette. Además, algunos pacientes con agresividad fueron tratados quirúrgicamente. Hay varios blancos estereotácticos descriptos para estos trastornos. La estimulación vagal puede ser usada también para depresión. Conclusión: Los resultados de la ECP en estos trastornos parecen alentadores. Sin embargo, se necesitan más estudios randomizados para establecer la efectividad de la CTC. Debe tenerse en cuenta que una apropiada selección de pacientes nos ayudará a realizar un procedimiento más seguro así como también a lograr mejores resultados quirúrgicos, conduciendo a la CTC a ser más aceptada por psiquiatras, pacientes y sus familias. Se necesita mayor investigación en varios temas como: fisiopatología de los trastornos del comportamiento, indicaciones de CTC y nuevos blancos quirúrgicos. PMID:25165612

Yampolsky, Claudio; Bendersky, Damian

2014-01-01

440

¿Qué es el Servicio de Información sobre el Cáncer del NCI?  

Cancer.gov

El Servicio de Información sobre el Cáncer (CIS) del Instituto Nacional del Cáncer (NCI) es un programa financiado con fondos del Gobierno Federal y fue establecido en 1975 como un componente fundamental de la misión y los programas de educación e información del cáncer del NCI. Comuníquese con nosotros para hablar con un especialista capacitado en información quien puede responder a sus preguntas relacionadas con el cáncer en inglés y español.

441

SOLICITUD DE PERMISOS PARA PUBLICAR EN LA WEB DE LA UA A la atencin del Director del Servicio de Informtica.  

E-print Network

SOLICITUD DE PERMISOS PARA PUBLICAR EN LA WEB DE LA UA A la atención del Director del Servicio de conozca): http://www.ua.es/ http://www.ua.es/ http://www.ua.es/ http://www.ua.es/ BAJA DE PERMISOS en las siguientes direcciones web (en caso de que las conozca): http://www.ua.es/ http://www.ua

Escolano, Francisco

442

V339 Del (Nova Del 2013) is a weak non-super-soft X-ray source  

NASA Astrophysics Data System (ADS)

V339 Del (Nova Del 2013) is currently being monitored approximately daily by Swift-XRT. X-ray analysis has been complicated due to optical loading caused by photons from the very bright optical source. (For a discussion of optical loading in the XRT, see our help page.) At early times, the data were collected mainly in Windowed Timing mode to mitigate this issue, and no X-ray source was detected (ATel #5283, #5305, #5318).

Page, K. L.; Beardmore, A. P.

2013-09-01

443

Performance comparison of MoNA and LISA neutron detectors  

NASA Astrophysics Data System (ADS)

In 2002 eight primarily undergraduate institutions constructed and tested the Modular Neutron Array (MoNA) which has been used to detect high energy neutrons at the National Superconducting Cyclotron Laboratory (NSCL). Nine institutions have now designed, constructed and tested the Large-area multi-Institutional Scintillator Array (LISA) neutron detector which will be used at the NSCL and the future Facility for Rare Isotope Beams (FRIB). Both detectors are comprised of 144 detector modules. Each module is a 200 x 10 x 10 cm^3 bar organic plastic scintillator with a photomultiplier tube mounted on each end. Using cosmic rays and a gamma source, we compared the performance of MoNA and LISA by using the same electronics to check light attenuation, position resolution, rise times, and cosmic ray peak widths. Results will be presented.

Purtell, Kimberly; Rethman, Kaitlynne; Haagsma, Autumn; Finck, Joseph; Smith, Jenna; Snyder, Jesse

2010-11-01

444

The Offline Software Framework of the NA61/SHINE Experiment  

NASA Astrophysics Data System (ADS)

NA61/SHINE (SHINE = SPS Heavy Ion and Neutrino Experiment) is an experiment at the CERN SPS using the upgraded NA49 hadron spectrometer. Among its physics goals are precise hadron production measurements for improving calculations of the neutrino beam flux in the T2K neutrino oscillation experiment as well as for more reliable simulations of cosmic-ray air showers. Moreover, p+p, p+Pb and nucleus+nucleus collisions will be studied extensively to allow for a study of properties of the onset of deconfinement and search for the critical point of strongly interacting matter. Currently NA61/SHINE uses the old NA49 software framework for reconstruction, simulation and data analysis. The core of this legacy framework was developed in the early 1990s. It is written in different programming and scripting languages (C, pgi-Fortran, shell) and provides several concurrent data formats for the event data model, which includes also obsolete parts. In this contribution we will introduce the new software framework, called Shine, that is written in C++ and designed to comprise three principal parts: a collection of processing modules which can be assembled and sequenced by the user via XML files, an event data model which contains all simulation and reconstruction information based on STL and ROOT streaming, and a detector description which provides data on the configuration and state of the experiment. To assure a quick migration to the Shine framework, wrappers were introduced that allow to run legacy code parts as modules in the new framework and we will present first results on the cross validation of the two frameworks.

Sipos, Roland; Laszlo, Andras; Marcinek, Antoni; Paul, Tom; Szuba, Marek; Unger, Michael; Veberic, Darko; Wyszynski, Oskar

2012-12-01

445

Na,K-ATPase: Isoform structure, function, and expression  

Microsoft Academic Search

An interesting feature of the Na,K-ATPase is the multiplicity of a and ß isoforms. Three isoforms exist for the a subunit, a1, a2, and a3, as well for the ß subunit, ß1, ß2, and ß3. The functional significance of these isoforms is unknown, but they are expressed in a tissue- and developmental-specific manner. For example, all three isoforms of the

Jerry B. Lingrel

1992-01-01

446

Background understanding and improvement in NaI scintillators  

NASA Astrophysics Data System (ADS)

Sodium Iodide scintillators are very interesting particle and radiation detectors. Low background requirements could limit their application in a variety of fields. We report the e.orts to understand and reduce the background in a set of 14 NaI detectors, stored underground since 1988, undertaken in the frame of the ANAIS experiment [1] in several directions, including PSD techniques, Monte Carlo simulations and detector upgrading.

Amaré, J.; Beltrán, B.; Carmona, J. M.; Cebrián, S.; García, E.; Gómez, H.; Irastorza, I. G.; Luzón, G.; Martínez, M.; Morales, J.; Ortiz de Solórzano, A.; Pobes, C.; Puimedón, J.; Rodríguez, A.; Ruz, J.; Sarsa, M. L.; Torres, L.; Villar, J. A.

2006-05-01

447

Radiation-induced creep of confined NaCI  

Microsoft Academic Search

Samples of pure single crystals of NaC1 and of a natural rock salt were simultaneously gamma-irradiated at an approximate constant dose rate (15 kGy\\/h) and a constant temperature (100°C) and for different lengths of time, resulting in integrated doses ranging from 0.02 to 44.6 MGy. Microstructural analysis showed that both incipient deformation structures and very advanced recovery structures develop during

A. García Celma; H. Donker

1994-01-01

448

Mode coupling in low NA plastic optical fibers  

NASA Astrophysics Data System (ADS)

Using the power flow equation and experimental measurements, investigated in this article is the state of mode coupling in low NA (0.3) step-index plastic optical fibers for laser beam launch. Results show the coupling length Lc at which the equilibrium mode distribution is achieved and the length zs of the fiber required for achieving the steady-state mode distribution. Numerical results obtained using the power flow equation agree well with experimental measurements.

Savovi?, Svetislav; Kova?evi?, Milan S.; Djordjevich, Alexandar; Baji?, Jovan S.; Stupar, Dragan Z.; Stepniak, Grzegorz

2014-08-01

449

Third-Order Elastic Constants of NaF  

Microsoft Academic Search

The complete set of third-order elastic constants for single crystals of NaF was determined from the hydrostatic-pressure and uniaxial-stress derivatives of natural sound velocities measured with a two-crystal ultrasonic-interference technique. There appeared to be no dislocation motion during the uniaxial measurements since changes in the natural sound velocities with stress were linear, and data recorded before and after a gamma

W. A. Bensch

1972-01-01

450

Two-frequency lidar technique for mesospheric Na temperature measurements  

Microsoft Academic Search

The authors describe a new two-frequency lidar for measuring Na temperature profiles that uses a stabilized cw single-mode dye laser oscillator (rms frequency jitter < 1 MHz) followed by a pulsed-dye power amplifier (140 MHz FWHM linewidth) which is pumped by an injection-locked Nd:YAG laser. The laser oscillator is tuned to the two operating frequencies by observing the Doppler-free structure

C. Y. She; H. Latifi; J. R. Yu; R. J. II Alvarez; R. E. Bills; C. S. Gardner

1990-01-01

451

NaCl-induced accelerated oxidation of a titanium alloy  

Microsoft Academic Search

The effect of a surface deposit of NaCl on the oxidation characteristics of a high-temperature titanium alloy was studied in the temperature range of 400–600°C. The influence of the water vapor content in the oxidizing environment was examined in the light of an existing electrochemical mechanism proposed for the hot-salt stress-corrosion-cracking phenomenon found in titanium alloys. It was established that

P. Dumas; C. St. John

1976-01-01

452

Na+ channel aggregation in remyelinating mouse sciatic axons following transection.  

PubMed

Mouse sciatic nerves from the degeneration-resistant strain C57BL/6/Wld (Ola) were surgically injected with lysolecithin to induce focal demyelination. Three days later they were transected adjacent to the spinal cord to eliminate contact of the axons with their cell bodies. The Na+ channel distribution was assessed by immunocytochemistry and followed at several stages of remyelination. Control experiments were performed on nerves that were injected but not cut. At (3 + 4) days, namely, nerves cut 3 days post-injection and examined 4 days after cutting, axons contained fully demyelinated regions. Na+ channel clusters appeared only at heminodes and at isolated sites that are likely to represent original nodes of Ranvier. During the next few days proliferating Schwann cells adhered to the axons and extended their processes. Clusters of Na+ channels appeared at their edges, and as the Schwann cells elongated the distance between these aggregates increased. A few clusters associated with neighboring Schwann cells approached each other and appeared to coalesce at sites where presumably new nodes of Ranvier would be formed. Beyond (3 + 6) days excessive degeneration of the transected axons precluded further observations. In the uncut controls, the spatio-temporal sequence of Schwann cell proliferation and channel patch formation and movement was similar to that described above, although myelin formation was somewhat faster than in the cut axons. It is concluded that Na+ channel aggregation associated with the early stages of remyelination is not dependent upon continuous communication of the axon with its cell body and is under local control. PMID:8567070

Tzoumaka, E E; Novakovi?, S D; Levinson, S R; Shrager, P

1995-10-01

453

Uptake and reaction of HOBr on frozen and dry NaCl/NaBr surfaces between 253 and 233 K  

NASA Astrophysics Data System (ADS)

The uptake and reaction of HOBr with frozen salt surfaces of variable NaCl / NaBr composition and temperature were investigated with a coated wall flow tube reactor coupled to a mass spectrometer for gas-phase analysis. HOBr is efficiently taken up onto the frozen surfaces at temperatures between 253 and 233 K where it reacts to form the di-halogens BrCl and Br2, which are subsequently released into the gas-phase. The uptake coefficient for HOBr reacting with a frozen, mixed salt surface of similar composition to sea-spray was 10-2. The relative concentration of BrCl and Br2 released to the gas-phase was found to be strongly dependent on the ratio of Cl- to Br - in the solution prior to freezing / drying. For a mixed salt surface of similar composition to sea-spray the major product at low conversion of surface reactants (i.e. Br - and Cl-) was Br2. Variation of the pH of the NaCl / NaBr solution used to prepare the frozen surfaces was found to have no significant influence on the results. The observations are explained in terms of initial formation of BrCl in a surface reaction of HOBr with Cl-, and conversion of BrCl to Br2 via reaction of surface Br -. Experiments on the uptake and reaction of BrCl with frozen NaCl / NaBr solutions served to confirm this hypothesis. The kinetics and products of the interactions of BrCl, Br2 and Cl2 with frozen salt surfaces were also investigated, and lower limits to the uptake coefficients of > 0.034, >0.025 and >0.028 respectively, were obtained. The uptake and reaction of HOBr on dry salt surfaces was also investigated and the results closely resemble those obtained for frozen surfaces. During the course of this study the gas diffusion coefficients of HOBr in He and H2O were also measured as (273 ± 1) Torr cm2 s-1 and (51 ± 1) Torr cm2 s-1, respectively, at 255 K. The implications of these results for modelling the chemistry of the Arctic boundary layer in springtime are discussed.

Adams, J. W.; Holmes, N. S.; Crowley, J. N.

2002-04-01

454

Grant Title: POSTDOCTORAL FELLOWSHIP IN MENTAL HEALTH AND SUBSTANCE ABUSE SERVICES Funding Opportunity Number: NA  

E-print Network

Grant Title: POSTDOCTORAL FELLOWSHIP IN MENTAL HEALTH AND SUBSTANCE ABUSE SERVICES (MHSAS) Funding Opportunity Number: NA Agency/Department: American Psychological Association (APA), Substance Abuse and Mental health and substance abuse services and research. Release and Expiration: NA Application Deadline

Farritor, Shane

455

Factors influencing skeletal muscle Na+, K+-ATPase and Plasma [K+] during exercise in humans.  

E-print Network

??The sodium-potassium adenosine triphosphatase enzyme (Na+,K+ -ATPase) regulates muscle cell [Na+],[K+] and muscle membrane potential, therefore playing a fundamental role in muscle excitability. This dissertation… (more)

Fraser, Steven Francis

2000-01-01

456

Preferential Interaction of Na+ over K+ to Carboxylate-functionalized Silver Nanoparticles  

EPA Science Inventory

Elucidating mechanistic interactions between specific ions (Na+/ K+) and nanoparticle surfaces to alter particle stability in polar media has received little attention. We investigated relative preferential binding of Na+ and K+ to carboxylate-functionalized silver nanoparticles ...

457

Subunit Dependence of Na Channel Slow Inactivation and Open Channel Block in Cerebellar Neurons  

E-print Network

inactivation, slow inactivation, and open-channel block, we recorded voltage-clamped, tetrodotoxin-sensitive Na firing depends on specialized voltage-gated channels. These include tetrodotoxin (TTX)- sensitive Na

Raman, Indira M.

458

Solvation of Na+, K+, and their dimers in helium.  

PubMed

Helium atoms bind strongly to alkali cations which, when embedded in liquid helium, form so-called snowballs. Calculations suggest that helium atoms in the first solvation layer of these snowballs form rigid structures and that their number (n) is well defined, especially for the lighter alkalis. However, experiments have so far failed to accurately determine values of n. We present high-resolution mass spectra of Na(+)He(n), K(+)He(n), Na(2)(+)He(n) and K(2)(+)He(n), formed by electron ionization of doped helium droplets; the data allow for a critical comparison with several theoretical studies. For sodium and potassium monomers the spectra indicate that the value of n is slightly smaller than calculated. Na(2)(+)He(n) displays two distinct anomalies at n=2 and n=6, in agreement with theory; dissociation energies derived from experiment closely track theoretical values. K(2)(+)He(n) distributions are fairly featureless, which also agrees with predictions. PMID:22374575

An der Lan, Lukas; Bartl, Peter; Leidlmair, Christian; Jochum, Roland; Denifl, Stephan; Echt, Olof; Scheier, Paul

2012-04-01

459

The local distribution of Na I interstellar gas  

NASA Technical Reports Server (NTRS)

We present high-resolution absorption measurements (lambda/Delta lambda approximately 75,000) of the interstellar Na I D lines at 5890 A toward 80 southern hemisphere early-type stars located in the local interstellar medium (LISM). Combining these results with other sodium measurements taken from the literature, we produce galactic maps of the distribution of neutral sodium column density for a total of 293 stars generally lying within approximately 250 pc of the Sun. These maps reveal the approximate shape of the mid-plane contours of the rarefied region of interstellar space termed the Local Bubble. Its shape is seen as highly asymmetric, with a radius ranging from 30 to 300 pc, and with an average radius of 60 pc. Similar plots of the Galactic mid-plane distribution of sources emitting extreme ultraviolet radiation show that they also trace out similar contours of the Local Bubble derived from Na I absorption measurements. We conclude that the Local Bubble absorption interface can be represented by a hydrogen column density, Nu(sub ETA) = 2 x 10(exp 19) cm(exp -2), which explains both the local distribution of Na I absorption and the observed galactic distribution of extreme ultraviolet sources. The derived mid-plane contours of the Bubble generally reproduce the large-scale features carved out in the interstellar medium by several nearby galactic shell structures.

Welsh, B. Y.; Craig, N.; Vedder, P. W.; Vallerga, J. V.

1994-01-01

460

Xylanase recovery by ethanol and Na2SO4 precipitation.  

PubMed

Xylans are the major components of the hemicellulosic fraction of lignocellulosic biomass and their hydrolysis can be obtained using xylanases from Penicillium janthinellum. In this work, sugarcane bagasse hemicellulosic hydrolysate was used as the substrate for producing xylanase. The precipitation of these enzymes was studied using ethanol and Na2SO4 as precipitating agents. Ethanol precipitation experiments were performed batchwise in concentrations ranging from 10 to 80%, pH 4.0 to 7.0, at 4 degrees C. The concentrations used in the precipitations with Na2SO4 were from 5 to 60% at pH 5.5 and 25 degrees C. Solubility curves as a function of xylanase activity and total protein for both precipitating agents were made. According to the results, Na2SO4 is not appropriate for precipitating xylanases in this medium since at salt concentrations higher than 25%, the enzyme was denaturated and at this concentration less than 80% of the enzyme and total protein were precipitated. Because of differences in xylanase and total protein solubility, a fractionated precipitation using ethanol can be performed, since with 40% ethanol, 49% of the total protein was precipitated and more than 95% of the enzyme was kept in solution. On the other hand approx 100% of the xylanases were recovered by precipitation after adding 80% ethanol. PMID:18576030

Cortez, E V; Pessoa, A; Assis, A N

1998-01-01

461

0.0 -8 objectius pel mil.lenni A la Cimera del Millenni, celebrada l'any 2000, el conjunt dels Estats  

E-print Network

a b 0.0 - 8 objectius pel mil.lenni A la Cimera del Mil·lenni, celebrada l'any 2000, el conjunt dels Estats membres de les Nacions Unides van aprovar la Declaració del Mil·lenni, en la qual: Van considerar com a valors fonamentals del nou mil·lenni: q La llibertat q La igualtat q La solidaritat q La

Oro, Daniel

462

Publicaciones del IGME: serie Hidrogeologa y aguas subterrneas, n 14. VI Simposio del Agua en Andaluca. II: 1.229-1.236. 2005  

E-print Network

Publicaciones del IGME: serie Hidrogeología y aguas subterráneas, nº 14. VI Simposio del Agua en Andalucía. II: 1.229-1.236. 2005 Sobre la calidad físico-química de las aguas superficiales del área metropolitana de Granada Sánchez Díaz, Luis* y Castillo Martín, Antonio** * Instituto del Agua. Universidad de

Castillo, Antonio

463

Aldosterone Regulates Na,K-ATPase and Increases Lung Edema Clearance in Rats  

Microsoft Academic Search

Aldosterone increases the Na,K-ATPase function in renal cells involved in active Na 1 transport. Be- cause the alveolar type 2 (AT2) cells participate in active Na 1 transport, we studied whether aldoster- one regulates the Na,K-ATPase in rat AT2 cells and whether aldosterone delivered by aerosols to spontaneously breathing rats affects edema clearance in a model of isolated-perfused lungs. The

WALTER G. OLIVERA; DAVID E. CICCOLELLA; NORA BARQUIN; KAREN M. RIDGE; DAVID H. RUTSCHMAN; DONOVAN B. YEATES; JACOB I. SZNAJDER

2000-01-01

464

Ion permeation in normal and batrachotoxin-modified Na+ channels in the squid giant axon  

Microsoft Academic Search

Na + permeation through normal and batrachotoxin (BTX)-modified squid axon Na ÷ channels was characterized. Unmodified and toxin-modified Na ÷ channels were studied simultaneously in outside-out membrane patches using the cut-open axon technique. Current-voltage relations for both normal and BTX- modified channels were measured over a wide range of Na ÷ concentrations and voltages. Channel conductance as a function of

ANA M. CORREA; RAMON LATORRE; FRANCISCO BEZANILLA

1991-01-01

465

The effect of NaCl on proline accumulation in rice leaves  

Microsoft Academic Search

The regulation of proline accumulation in detached leaves of rice(Oryza sativa cv. Taichung Native 1) was investigated.Increasing concentrations of NaCl from 50 to 200 mM progressivelyincreased proline content in detached rice leaves. NaCl induced prolineaccumulation was mainly due to the effect of both Na+ andCl- ions. Proline accumulation caused by NaCl was related toprotein proteolysis, an increase in ornithine-d-aminotransferaseactivity,a decrease

Chuan Chi Lin; Yi Ting Hsu; Ching Huei Kao

2002-01-01

466

Cryptosin induces backbone structural changes in cardiac Na+ and K+ dependent adenosinetriphosphatase.  

PubMed

Cryptosin, a new cardenolide, was found to preferentially bind to Na,K-ATPase enzyme (7), which is believed to be the ouabain binding site on cardiac sarcolemmal membrane. CD spectral studies revealed that cryptosin, in the presence of Na+ and Mg++ ions, bind to Na,K-ATPase and induce a dose-dependent change in the backbone structure of cardiac Na,K-ATPase. PMID:1965277

Venkateswara, R R; Dipak, D; Banning, J W; Vaidyanathan, C S

1990-10-01

467

Caustic Recycle from Hanford Tank Waste Using Large Area NaSICON Structures (LANS)  

SciTech Connect

This report presents the results of a 5-day test of an electrochemical bench-scale apparatus using a proprietary (NAS-GY) material formulation of a (Na) Super Ion Conductor (NaSICON) membrane in a Large Area NaSICON Structures (LANS) configuration. The primary objectives of this work were to assess system performance, membrane seal integrity, and material degradation while removing Na from Group 5 and 6 tank waste from the Hanford Site.

Fountain, Matthew S.; Sevigny, Gary J.; Balagopal, S.; Bhavaraju, S.

2009-03-31

468

Differential blockade of neuronal voltage-gated Na + and K + channels by antidepressant drugs  

Microsoft Academic Search

The effects of a range of antidepressants were investigated on neuronal voltage-gated Na+ and K+ channels. With the exception of phenelzine, all antidepressants inhibited batrachotoxin-stimulated 22Na+ uptake, most likely via negative allosteric inhibition of batrachotoxin binding to neurotoxin receptor site-2 on the Na+ channel. Imipramine also produced a differential action on macroscopic Na+ and K+ channel currents in acutely dissociated

Graham M Nicholson; Tim Blanche; Kylie Mansfield; Yvonne Tran

2002-01-01

469

Na8Au9.8(4)Ga7.2 and Na17Au5.87(2)Ga46.63: The diversity of pseudo 5-fold symmetries in the Na-Au-Ga system  

NASA Astrophysics Data System (ADS)

The Na-rich part (~30% Na) of the Na-Au-Ga system between NaAu2, NaGa4, and Na22Ga39 has been found to contain the ternary phases Na8Au9.8(4)Ga7.2 (I) and Na17Au5.87(2)Ga46.63 (II), according to the results of single crystal X-ray diffraction measurements. I is orthorhombic, Cmcm, a=5.3040(1), b=24.519(5), c=14.573(3) Å, and contains a network of clusters with local 5-fold symmetry along the a-axis. Such clusters are frequent building units in decagonal quasicrystals and their approximants. II is rhombohedral, R3¯m, a=16.325(2), c=35.242(7) Å, and contains building blocks that are structurally identical to the Bergman-type clusters as well as fused icosahedral units known with active metals, triels and late transition elements. II also contains a polycationic network with elements of the clathrate V type structure. Tight-binding electronic structure calculations using linear muffin-tin-orbital (LMTO) methods on idealized models of I and II indicate that both compounds are metallic with evident pseudogaps at the corresponding Fermi levels. The overall Hamilton bond populations are generally dominated by Au-Ga and Au-Au bonds in I and by Ga-Ga bonds in II; moreover, the Na-Au and Na-Ga contributions in I are unexpectedly large, ~20% of the total. A similar involvement of sodium in covalent bonding has also been found in the electron-richer i-Na13Au12Ga15 quasicrystal approximant.

Smetana, Volodymyr; Corbett, John D.; Miller, Gordon J.

2013-11-01

470

La reparación del daño como mecanismo de tutela de la persona. Del daño a la salud a los nuevos daños extrapatrimoniales  

Microsoft Academic Search

En la actualidad, el operador del Derecho se enfrenta a dos de los más importantes problemas del nuevo derecho de daños: por un lado, la clasificación del perjuicio y, por el otro, la reparación correspondiente a cada una de sus categorías, que debe estar informada por el principio de reparación integral, y que impone en consecuencia considerar más que las

Milagros Koteich Khatib

471

Ingenieros militares en España en el siglo XIX. Del arte de la guerra en general a la profesión del ingeniero en particular  

Microsoft Academic Search

Esta comunicación tiene por objeto mostrar las diferentes opciones profesionales del Cuerpo de Ingenieros Militares español durante el siglo XIX. Una corporación técnica y facultativa que desde principios del ochocientos perdió algunas competencias del campo de la ingeniería civil. En este trabajo señalaremos la adaptación de los mecanismos de selección de estos ingenieros y las reivindicaciones que realizaron para equipararse

José Ignacio Muro Morales

2007-01-01

472

Na+-transport modulation induces isoform-specific expression of Na+,K+ATPase ?-subunit isoforms in C2C12 skeletal muscle cell  

Microsoft Academic Search

Changes in demands for Na+ transport alter expression of the Na+,K+-ATPase subunit isoforms. In skeletal muscle, the effects of these changes on expression the a2 isoform, the major isoform expressed in differentiated muscle cell, is not known. Therefore, this study examines regulation of the a-subunit isoforms by Na+ in the C2C12 skeletal muscle cell that expresses the a1 and a2

Richard Ladka; Yuk-Chow Ng

2000-01-01

473

ROS-mediated vascular homeostatic control of root-to-shoot soil Na delivery in Arabidopsis  

PubMed Central

Sodium (Na) is ubiquitous in soils, and is transported to plant shoots via transpiration through xylem elements in the vascular tissue. However, excess Na is damaging. Accordingly, control of xylem-sap Na concentration is important for maintenance of shoot Na homeostasis, especially under Na stress conditions. Here we report that shoot Na homeostasis of Arabidopsis thaliana plants grown in saline soils is conferred by reactive oxygen species (ROS) regulation of xylem-sap Na concentrations. We show that lack of A. thaliana respiratory burst oxidase protein F (AtrbohF; an NADPH oxidase catalysing ROS production) causes hypersensitivity of shoots to soil salinity. Lack of AtrbohF-dependent salinity-induced vascular ROS accumulation leads to increased Na concentrations in root vasculature cells and in xylem sap, thus causing delivery of damaging amounts of Na to the shoot. We also show that the excess shoot Na delivery caused by lack of AtrbohF is dependent upon transpiration. We conclude that AtrbohF increases ROS levels in wild-type root vasculature in response to raised soil salinity, thereby limiting Na concentrations in xylem sap, and in turn protecting shoot cells from transpiration-dependent delivery of excess Na. PMID:23064146

Jiang, Caifu; Belfield, Eric J; Mithani, Aziz; Visscher, Anne; Ragoussis, Jiannis; Mott, Richard; Smith, J Andrew C; Harberd, Nicholas P

2012-01-01

474

Potential curves for Na2/+/ and resonance charge transfer cross sections.  

NASA Technical Reports Server (NTRS)

A mode potential method, applied earlier to the positively charged diatomic lithium molecule Li2(+), is used to calculate the six lowest potential energy curves of Na2(+). Charge transfer cross sections are calculated for Li(+) on Li and for Na(+) on Na and found to be in reasonable agreement with experiment.

Bottcher, C.; Allison, A. C.; Dalgarno, A.

1971-01-01

475

On the locus of action of Na + at site I of oxidative phosphorylation  

Microsoft Academic Search

The effect of octylguanidine on the Na+ stimulated oxygen uptake of rat liver mitochondria and bovine heart submitochondrial particles and on the Na+ induced efflux of K from the mitochondria has been examined. The results indicate that the action of Na+ is inhibited by octylguanidine, but that the degree of inhibition depends on the concentration of the cation. Apparently, a

A. Gómez-Puyou; F. Sandoval; M. Tuena De Gómez-Puyou; E. Chávez; E. Pinto

1972-01-01

476

Expression of Cardiac Na Channels with Appropriate Physiological and Pharmacological Properties in Xenopus Oocytes  

Microsoft Academic Search

The objective of this study was to determine whether the Xenopus laevis oocyte can express an exogenous cardiac Na channel that retains its normal physiological and pharmacological properties. Cardiac Na channels were expressed in oocytes following injection of RNA from guinea pig, rat, and human heart and detailed analysis was performed for guinea pig cardiac Na channels. Average current amplitudes

D. S. Krafte; W. A. Volberg; K. Dillon; A. M. Ezrin

1991-01-01

477

Glycosaminoglycan polymerization may enable osmotically inactive Na+ storage in the skin.  

PubMed

Osmotically inactive skin Na(+) storage is characterized by Na(+) accumulation without water accumulation in the skin. Negatively charged glycosaminoglycans (GAGs) may be important in skin Na(+) storage. We investigated changes in skin GAG content and key enzymes of GAG chain polymerization during osmotically inactive skin Na(+) storage. Female Sprague-Dawley rats were fed a 0.1% or 8% NaCl diet for 8 wk. Skin GAG content was measured by Western blot analysis. mRNA content of key dermatan sulfate polymerization enzymes was measured by real-time PCR. The Na(+) concentration in skin was determined by dry ashing. Skin Na(+) concentration during osmotically inactive Na(+) storage was 180-190 mmol/l. Increasing skin Na(+) coincided with increasing GAG content in cartilage and skin. Dietary NaCl loading coincided with increased chondroitin synthase mRNA content in the skin, whereas xylosyl transferase, biglycan, and decorin content were unchanged. We conclude that osmotically inactive skin Na(+) storage is an active process characterized by an increased GAG content in the reservoir tissue. Inhibition or disinhibition of GAG chain polymerization may regulate osmotically inactive Na(+) storage. PMID:14975935

Titze, Jens; Shakibaei, Mehdi; Schafflhuber, Markus; Schulze-Tanzil, Gundula; Porst, Markus; Schwind, Karl H; Dietsch, Peter; Hilgers, Karl F

2004-07-01

478

Comparison of meteor radar and Na Doppler lidar measurements of winds in the mesopause region  

E-print Network

Comparison of meteor radar and Na Doppler lidar measurements of winds in the mesopause region above 29 January 2005. [1] Simultaneous sodium (Na) Doppler lidar and meteor radar measurements/s at altitudes below 96 km. This is smaller than the RMS differences observed in a previous Na lidar and meteor

Chu, Xinzhao

479

Componentes naturales y de uso del suelo vulnerables a las variaciones del nivel del mar en la costa atlántica de México  

Microsoft Academic Search

Palabras clave Regionalizaci6n de costas, fislografia, vulnerabilidad costera, uso del suelo Absúact Geomorphological alaradenstia of the mastal iongitudinal prn* and the arrangwent of the physiographical stmcture allowed the rmnition of two zonas: a) the intertidai zone -a basic sntne for dired imoaci of sea leve1 dame: and b) an adjacent peritidál (supralittoral) hnge &n area of cushioning or of polential

Mano Arturo; Ortiz Pérez; Ana Patricia; Méndez Linares

480

Elevated levels of glucose and L-fucose reduce 22Na+ uptake and whole cell Na+ current in cultured neuroblastoma cells.  

PubMed

Na+ flux was studied in cultured neuroblastoma cells grown in medium containing increased glucose or L-fucose concentrations. Chronic exposure of neuroblastoma cells to 30 mM glucose or 30 mM L-fucose caused a decrease in ouabain-sensitive and veratridine-stimulated 22Na+ uptake compared with cells cultured in unsupplemented medium. The Na+ current, determined by using whole-cell configuration of the patch clamp, was also decreased in these cells. Tetrodotoxin (3 microM), which blocked whole cell Na+ currents, also blocked veratridine-stimulated 22Na+ accumulation. Culturing cells in medium containing 30 mM fructose as an osmotic control had no effect on Na+ flux. Specific [3H]saxitoxin binding was not affected by 30 mM glucose or 30 mM L-fucose compared with cells grown in unsupplemented medium, suggesting that the number of Na+ channels was not decreased. These studies suggest that exposing cultured neuronal cells to conditions that occur in the diabetic milieu alters Na+ transport and Na(+)-channel activity. PMID:8263545

Yorek, M A; Stefani, M R; Wachtel, R E

1994-01-01

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